JS1k: The JavaScript code golfing competition

2010 - The Original

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Check out demos from previous editions too! 2011 , 2012 , 2013 , 2014 , 2015 , 2016 , 2017 , 2018 , 2019

By Romain Huet
( @romainhuet, website )

Move the ball through the game using the mouse cursor. Try to collect as many coins as you can before the time is over, and make sure the ball doesn't drop through any holes! Warning: directions are r…

By Ilan Bar-Magen

It was suppose to be a game called "Circles vs. Squares" where a circle shoots around squares enemies. Well, I didn't find the time (and space) to add the squares :) so it is apparently became just a…

By Tobias Bräutigam
( @tbraeutigam, website )

Play memory! Version 2.0 with fixed layout + color :-)

By carlocci
( website )

javascript theremin

By Rob O'Dwyer
( @odwyerrob, website )

Displays random fading unicode characters in fancy colors.

By bartaz
( @bartaz )

Draws basic fractal (I forgot it's name). Click to draw next degree... Beware - if you go farer than 10 clicks or so it may kill your browser ;)

By Lee
( @leegao, website )

A simple text editor that automatically highlights Javascript code in the textarea as you type. (an edit-in-place syntaxhighlighter)

By Shah Pavel Jamal
( website )

Night scene. Procedural trees, grass, shooting stars and the moon. Click anywhere to shoot a star.

By h3nr1x
( @h3nr1x )

DanceHero, a simplified version of a Dance Dance Revolution like game (kind of)

By Mark de Jong
( @spellcoder, website )

An (text)sinescroller and 2d starfield inspired by old Amiga cracktro's which often came with cracked games in the early 1990's.

By Christian Bonham
( website )

Music Related:

By Peter Liepa
( @peterliepa, website )

A game. The objective of each level is to get the water level to the top of the screen. Water is displaced by green beach balls, which are created and expanded by pressing and holding the mouse button…

By Bjoern Paschen
( @prypjat )

Just a simple Raycasting Engine (you know, Wolfenstein 3D ;) )

By Juan Carlos Clemente
( @_zetta, website )

Another improvement v0.5 of 1kBoomshine

By Chris Smoak
( @chrissmoak )

Creates and plays a WAV or MP3 (depending on browser) of your message encoded in Morse code.

By Unkulunkulu
( @arokanto )

An examination into golden ratio, inspired by Simppa's LoopPump Flash-demo: http://www.simppa.fi/experimental/as3/2009/math/LoopPump/

By z0va
( @z0va, website )

v3.0 Game is now a "papy jump" like

By Bernard Schmitz
( website )

Flame demo

By Chris Waalberg
( @chriswaalberg, website )

Imagine creating a watercolor painting with a thousand tiny, living brushes. That's what this is. Let it run for a while and use your mouse to lure the brushes. Or don't and let them paint on their ow…

By ThatOneGuy
( @bryanblakey )

Turns the browser window into the Matrix. Press "s" to start/stop the generation of new matrix entities.

By Sebastian Sprenger

Quine Shooter

By Adriano Ueda
( @adriueda )

A sokoban clone using ASCII. You're the man (@), trying to push the crates ($) on the goals (.). When a crate is on the goal, it becomes a (*).

By Jacob Seidelin
( @jseidelin, website )

Planet #1024

By Keon Ahn
( @graciasa, website )

Blockhead's Gomoku (Five in a Row)

By Kobus Pretorius
( @kbpret )

2D Bump Map Putty

By Gabriel Gambetta
( website )

Raytracer with spheres, point lights, ambient, diffuse and specular lighting, shadows, and reflective surfaces. Tested in Firefox and Chrome, works much faster in Chrome.

By Gabor Nagy

Space Invaders Game v0.3

By dragal

Generates the Mandelbrot fractal and corresponding Julia sets.

By Benji Schwartz-Gilbert
( website )

Canvas based JavaScript command line

By Mark Rhodes
( @markncrhodes )

A Lotto number picker - let the bugs decide!

By satan

random world. click to start a fire.

By yutt

Creates a cityscape.

By Christian Krebs
( @__chris__, website )

The flying carpet. A little contemplative recreational experiment with the RGB color cube.

By Øyvind Smestad
( @osmestad )

SVGMan, a simple PacMan inspired game in SVG. Use arrow keys to move.

By vladmanea
( @vladmanea, website )

Enhanced spiral, highly customizable (see full source for details). Has approx. 5 chars left for you to use for customizing the values :) The values of 1 and the red color yield to a rose. Other value…

By Matt Papi

A match-three game, minus the jewels (and animations). Click two adjacent boxes to swap them, 3 or more of the same color in a row scores.

By Tim Smith
( website )

Renders a random 3D landscape with lighting & aerial perspective.

By Tobias Prinz

Tagcloud driven by a simple 3D engine that features rotation matrices (x, y) and some simple camera translation. done without canvas. move your mouse.

By Tom Hargreaves

Draws a sunflower head, in a tweet-sized 140 characters (142 bytes)

By Rebecca
( @veubeke, website )

1k Turismo - an old school arcade racer. Use arrow keys to steer.

By Dex

By Jonas Höglund
( website )

Rainbow visual effect thingy. Click on it to go "fullscreen" (stretches canvas to screen edges).

By Pogocsan Florin

Alternate squares, fits in a tweet :)

By fazeaction
( @tribadelics, website )

2.5D flow field particle. Updated to 10K to 15K clipping points. Colorized particles.

By benny schuetz
( @bennyschuetz, website )

b!zarre arts.

By nrkn
( @nrknthuk, website )

Yellow vs. Red, a roguelike game. Movement with mouse. Enemies are red, health green, level exits black. Walls can be moved like sokoban. Gaining enough experience or clearing level gives you extra he…

By Jim Wagner

Interact to sculpt a poem

By halcy
( @halcy, website )

Raymarcher, flying through a torus field and a cube field, alternately, smoothly blending between the two, with soundtrack, and a few bytes to spare. Potentially a bit heavy on the CPU. ;) Much thanks…

By AlteredQualia
( @alteredq, website )

Boom - a remake of '80s classic arcade game Kaboom!

By Remco Veldkamp
( @remcoder )

/* WipeOut 1k */

By Mathieu 'p01' Henri
( @p01, website )

WOLF1K and the rainbow characters.

By Daniel Muller
( @asd5a )

Shiny discs in 3d space

( @OlivierHuet, website )

V2.1 : Added rotations (now 573 bytes)

By Aurelien Saussay
( @asaussay )

Falldown game, in 1K of javascript.

By Jason Brown
( @loktar00, website )

JSGrappler - You are a little pixel armed with a grapple cable, click to shoot it at the platforms, catch a platform to fling yourself higher. If you fall below the bottom (even while grappled-(featur…

By Nathan Young
( website )

pop the dom into bubbles then chase them with the mouse! Pointless fun!

By Paul Brunt
( @super_eggbert, website )

updated 3d particle system.

By Christopher McKenzie
( website )

Traditional, non-canvas coloring.

By Óscar Toledo G.
( @nanochess, website )

Tiny Chess.

By yent

(really) small 3d iso wire renderer thing

By Viktor Kelemen
( website )

Draws a fractal monster that you may find under your bed as well.

By AlteredQualia
( @alteredq, website )

High resolution animated 3d balls with brushed surface shading and depth-of-field effect (all fake).

By Jukka-Pekka Kekkonen
( @mdry )

Old school terrain scroller.

By Ian Sullivan

A puddle simulator - click anywhere to make it rain. It is a simulation of the 2D wave equation: (http://en.wikipedia.org/wiki/Wave_equation).

By Craig Sharkie
( @twalve )

A poem for the dyslexically inclined or something to keep your right brain entity-ertained. And it comes complete with an acrostic and a numeric pun.

By Jake Stothard

Simple sparkles with gravity.

By Mark de Jong
( @Spellcoder, website )

An (text)sinescroller and 2d starfield inspired by old Amiga cracktro's which often came with cracked games in the early 1990's.

By p4p4
( website )

the nautilus raymarcher,

By Shah Pavel Jamal
( website )

Procedural tree with shootings stars, night scene.

By dmitrig01
( @dmitrig01, website )

Move your player with the mouse, try to avoid the red dots, and the green dots give you (temporary) invulnerability. Your score is in the upper left hand corner. Based on Hakim El Hattab's Sinuous at…

By Sjoerd Visscher
( @sjoerd_visscher, website )


By Aki Jäntti

Scientifically (not) very accurate cloud time-lapse simulation.

By Chris Richards
( @ripter001, website )

Draws the Reddit Logo. :D

By Vladimir Carrer
( @vladocar, website )

Simply puts the grid around the visual browser surface divided by 100px.

By Pradheep Ravichandran

This is a simple maze game. The algorithm chooses a random starting point and random directions and continues till it reaches any end of horizontal axis.

By Philip Linde
( @boomlinde, website )

Simple bending ray demo effect in ASCII.

By Marcus van Houdt
( @marcusvanhoudt )

A homage to the Amiga Boing Ball, inspired by http://www.youtube.com/watch?v=-ga41edXw3A .

By Scriptin
( @scriptin, website )

CAR DRIVING SIMULATOR! Use arrow keys to drive.

By Chris Morris
( website )

An artillery duel modeled after Tank Wars. With a few necessary modifications, obviously.

By Tobias Schneider
( @tobeytailor, website )

Simple Color Picker

By TGGC/Bluflame
( website )

3D walk through a metaball Landscape. Can either be watched or used interactively. Pressing mousebutton builds up a growing metaball, which can be moved around.

By Ryan Day
( @soldair, website )

JS Piano - generates wav files on the client side.

By Patrick Walton
( @pcwalton, website )

Columns, the classic competitor to Tetris. Left and right arrow keys move; up cycles the order of the falling gems. Line up three matching colors in a row. Get combos and chains to score lots of point…

By Paulo Falcao
( @PauloFalcao, website )

Raymarching using Distance Fields

By Stuart Knightley
( @stuidge, website )

A simple jumping game based on the popular Canabalt.

By Óscar Toledo G.
( @nanochess, website )

Tiny Chess.

By Adis H
( @hamzadis )

The script draws a tree 3D perspective projected "cubes".

By Dan Newcome
( @dnewcome, website )

Mandelbrot set fractal rendering with simple color cycling effect. Colorizes values contained in the actual set for a water droplet skin effect animation.

By Premasagar Rose
( @premasagar, website )

~ PHI ~

By CmDev

Realtime rotating zoom into the mandelbrot fractal.

By Anwerso
( website )

Yet another "screensaver" on canvas.

By Mike Betten
( @betten, website )

Shoot the Vs as they fall. Use the mouse to move and click to shoot.

By John Smith
( website )

Single octave piano.

By Max Lovenheim Irwin

Square Chase - use your mouse to try and click the evading squares.

By Andrew Vehlies
( @avehlies )

Bounces some boxes around and uses gravity. Original code (with by hand minification): 1021 lines, minified down to 781.

By Jonathon Creenaune

Jump your way to JS glory.

By davebee

This demo try to mimic the 80's arcade game "STAR WARS", when Luke has to destroy the death star.

By Blake Callens
( @blakecallens, website )

v1.2 of Missile Command like game. Score is now alerted before game restarts. Use mouse to aim and shoot.

By Takacs Janos

This is a turn based two player car race game. We used to play this on squared paper in school during math class :) Poke around with your mouse to see the possible next steps. Try to stay on the road.…

By p4p4
( website )

grumpy gwrrrll.

By WAHa.06x36
( @waha_06x36, website )

Pulsating plasma ball effect.

By Luis Gonzalez
( @luis2048, website )

10 Unique Pixel Effects. Click to see them all.

By TotalDuke

Blazing fire with rotating blurry js1k text.

By Ryan Sandor Richards
( @rsandor, website )

Graphics only demo featuring colorful meandering strands.

By Sebastian

A living ecosystem of plants and worms in flatland.

By Kostas Symeonidis
( @ksymeon, website )

Sit back, relax and enjoy one of the shapes of "3D Dissolve".

By Particle Storm
( @varseb, website )

Particle storm in the cubic universe

By Aivo Paas
( @aivopaas )

Full-featured Tetris clone in 1K of JS

By Phil McCarthy
( @phl, website )

Simple water simulation based on cellular automata, with refraction and reflection rendering. Move mouse to make ripples.

By Eleasar

Morse code in a tweet ;)

By Felix Marin
( @fpmarin @plainjavascript, website )

We show a animated draw of a four corners Sierpinski polygon. It generalizes the usual Sierspinki triangle of fractal theory.

By Ideal Machine
( @idealmachine, website )

Television Simulator/Quine: A quine is a program that prints its own source code. However, that does *not* mean it is easy to read its printed output.

By Paul Mealy
( website )

Animated color-shifting waves.

By bga
( @bga_, website )

I see all competitors are making demos nicer and nicer, but my demo was just bump map of blurred letters :)

By Alexandre Abreu
( @AlexAbreuDev )

Simple, quick and dirty "two 3D advancing planes" raytraced with a 4x4 grid. The depth is taken into account.

By Peter van der Zee
( @kuvos, website )

It's a Brainfuck interpreter, including mini-IDE. It's heavily hand-tuned and finalized with the Microsoft Ajax Minifier. Brainfuck is a turing language with 8 commands, <>[]+-,. which operate on a st…

By Luis Toledo
( @digitalcth, website )

A simple breakout game.

By loot

A mix between brick breaker and pinball, featuring super cool animated bumpers! Use L and R arrow keys to play. Actually any key will work for L! (its not a bug its a code-reducing "feature") The game…

By cody s
( website )

This is a fish/bird flocking algorithm.

By Gabor Turi
( website )

Mandelbrot set with colors

By n3wjack
( @n3wjack, website )

It's all about the code. This script uses it's own code to supply the visuals. How cool is that?

By cody
( website )

Virtual Ants

By Yoyofr
( website )

Updated version of my mandelbrot zoomer : you can now specify the zoom depth (2^choice), the window size in pixels (square) & the zoom coordinates.

By Adam
( @AdamBurmister, website )

Particles in liquid. Give your mouse a swirl and try a click.

By Marijn Haverbeke
( @marijnjh, website )

Legend Of The Bouncing Beholder

By Paul Nicholls
( @NullColaShip, website )

ASCII-Art Mandelbrot explorer, ported from T-SQL to JavaScript and then compressed to 1K

By João Eiras
( @xErath )

Tetris game as close as possible to the original one. Ascii representation of pieces. Use arrows to play, allows dropping pieces with down. Lacks "game over" message due to size limit. No sound track…

By Kostas Michalopoulos
( @badsectoracula )

Its *Super Black Sphere Avoider 2D!* :-)

By Ben van Enckevort

Rain generator. Click to pin umbrella, any key to restart simulation.

By Scriptin
( @scriptin, website )

supposed to be a simulation of flight through illuminated tunnel =)

By Mathieu 'p01' Henri
( @p01, website )

tweet-sized entry: Embossed Mandelbrot Fractal rendered onto an HTML5 Canvas element

By Howard Yeend
( @user24, website )

cave updated again to fix reported firefox hang with setInterval(foo(),1);

By Pinhas

Cesar cipher (http://en.wikipedia.org/wiki/Caesar_cipher) encryption and decryption.

By Lars Rönnbäck
( website )

v1.0 First submission

By Pa7

This app encrypts a text (userinput) into a picture containing just alpha values which represent single characters. Decrypt by reading pixelwise and creating strings from charactercodes. E.g. you coul…

By Jonas Höglund
( website )

Just some flying particles, aiming for a certain point. Default is center of canvas, but if you hover over it, they'll follow the mouse.

By Heyscore
( @heyscoregames, website )

3D Heyscore Pong

By Alex Kloss

Rohrschach - a sort of reduced spirograph in 138 bytes

By Howard Yeend
( @puremango, website )

Another tweetable entry! This one really is stained glass :)

By iamtef
( @iamtef, website )

a zooming mandelbrot viewer

By Ziling Zhao
( website )

Snow flakes in a vector field. Wind happens about once every 10 seconds, wind reset after each wind occurs.

By Steve Guidetti
( @ultramegatech, website )

Lots of bouncy balls. Move the mouse and nearby balls will follow. Click and all the balls follow.

By Yuri Ivatchkocitch
( @y3i12, website )

Colorful Wavy Waves.

By AlteredQualia
( @alteredq, website )

High resolution animated 3d balls with brushed surface shading and depth-of-field effect (all fake).

By Tolito
( @tolito, website )

A simple version of Breakout/Arcanoid/etc... move with the cursor arrows.

By Piers Goodhew
( @piersg )

V 1.2 of sketch/paint app (I call it "mi canvas es su canvas")

By Matthieu

Little game :

By Howard Yeend
( @puremango, website )

Rot13 in a tweet - now shorter, and with more functionality!

By Luis Gonzalez
( @luis2048, website )

A rotating 3D computer wireframe v2.

By Stephan Seidt
( @evilhackerdude, website )

http://motherfuckinglasers.com/ done in canvas + animation

By strager - jazzyb
( @strager, website )

Tried to get something really interesting in 140 bytes. I wasn't successful, but I kept compressing the effect to what it is now. Enjoy.

By Jason Brown
( @loktar00, website )

To replace my previous vomit inducing demo, this one generates a cellular texture, which changes color and moves around. Larger windows have performance issues when using Firefox.

By Yoyofr
( website )

Final version of this wave/rubber fx : added 'elastic' like fx and better lightning. However, I had to simplify a bit the waves fx to match the 1024 bytes limit...

By hyperandroid
( @hyperandroid, website )

Nightly view of my garden grass animated by mild wind.

By Peter Liepa
( @peterliepa, website )

A goofy doodler that is evocative of contrails, bubbles, intestines. Use your mouse, experiment with stroke speed and shape.

By Martin Kaesberger
( website )

bouncing balls which explode after a while. for those exploded new balls appear after a while.

By Howard Yeend
( @puremango, website )

Tweet-sized blocks of colour. Colour choosing technique lifted from http://js1k.com/demo/230 ;)

By Howard Yeend
( @puremango, website )

A simple AllRGB entry in 1k. Generates an image containing every possible RGB colour.

By Alex Boone
( @aboone, website )

Play a game of draw poker. Use 1-5 number keys to choose which card(s) to discard, "Enter" to draw.

By Fireworks

By Stephen Cunliffe
( @scunliffe, website )

A 52 Card Pickup game gone wild! An infinite number of cards scatter on the table for pickup.

By Yoyofr
( website )

Another Mandelbrot fractal stuff, but this time with 'realtime' zoom. A bit slow to start, but after having clicked on the spot you want to zoom, will zoom smoothly from x1 to x65536.

By Stefan Trenkel

'Der springende Punkt' is here.

By Stefan Schneider-Kennedy
( website )

Generates interesting JS1K logos (in a tweet!). Updated with a more interesting shape, and decoupled the position from the shape (I could spare the bytes).

By Egon Elbre
( @egonelbre, website )

Draws some pretty images slowly.

By Martin Rohrmeier
( @OoyoO, website )

The poor progammer's 2D physics engine.

By Ron MacMuhu
( website )

EAN-13/UPC barcode renderer

By Rebecca
( @veubeke, website )


By Yoyofr
( website )

Final version (at least I hope...) : reduced a bit more code size so black background is

By Christopher Abad
( website )

It's a simple 8-bar tracker that generates on-the-fly mixing & generation of WAV files composed of multi-note bars at 4000/16/1.

By migerh
( @migerh )

a simple 2d function plotter. you can use some functions and constants like sin, cos, pow, ... (see demo itself). primitive x- and y-axes are drawn, you can even change the viewport.

By Nate Sigrist
( @NateSigrist )

Simulates the collision of 700 balls with conservation of momentum. The ball's mass is relative to its radius.

By Petar

Graphic representation of bubble sort

By spirit23
( website )

Whirling lines based on my old screensaver program:

By Luis Gonzalez
( @luis2048, website )

A rotating 3D computer wireframe.

By kadir pekel
( @kadirpekel, website )

Simple fun game aka Same Game

By Makram Saleh
( @msaleh, website )

A (very) simple number encryption/decryption.

By Dawid Kubiak
( @dawidkubiak, website )

polarity on text

By Andy Polhill
( @andrew_polhill, website )

Its the arcade classic BreakOut!

By spirit
( website )

random whirling lines base on my old screensaver code http://sourceforge.net/projects/win32scr/

By Guillaume Bort
( @playframework, website )

Colored isometric 3d objects that bounce on mouse over.

By Florian Bösch
( @pyalot, website )

The usual flying dots under gravity with color and size variation. The kicker's in the compression.

By rwbg

trippy metaballs really nothing fancy

By Eleasar

Morse code in a tweet ;)

By fanks
( @fankyou, website )

Your friend went to Stockholm for a vacation and you are in charge of keeping your mates fish alive.

By Guy Frost / DESiRE
( website )

Im/exploding particle logo with scrolltext.

By Mr Speaker
( @mrspeaker, website )


By Nick
( website )

A recreation of the Laughing Man from ghost In the shell, Updated to use the proper font. (If in linux make sure you have the msttcorefonts package installed.)

By Nick
( website )

A replication of the Laughing man from Ghost in the Shell.

By razorwolf

An updated copy of the windows Mystify screensaver

By Ideal Machine
( website )

Television Simulator/Quine: A quine is a program that prints its own source code. However, that does *not* mean it is easy to read its printed output.

By blaznyoght
( @blaznyoght )

Butterflies... When prompted, type in a value around 500 if you want something nice.

By blaznyoght
( @blaznyoght )


By nic
( @nicrizzo, website )

My old broken TV, grayscale again, in a tweet :)

By Guy Frost / DESiRE
( website )

Im/exploding particle logo

By Luhr Løvdahl

Visualizations of iterations of candidates (along a random straight line) for Julia sets defined by the quadratic polynomials.

By Guy Frost / DESiRE
( website )

Exploding/imploding particle logo.

By Marcus van Houdt
( @marcusvanhoudt )

The Amiga boing ball, as seen here http://www.youtube.com/watch?v=-ga41edXw3A, although this time in actual 3D: a camera rotation instead of a palette rotation.

By Nate Sigrist
( @NateSigrist )

simulation of collisions of 700 balls with conservation of momentum. The radius of the ball is it's mass.

By H. Lacherstorfer
( website )

Minesweeper. Fixed height+length. Approx. 10-15 mines hidden. No timer. If you click on mine you loose (red cell) and gameboard is revealed. If you click on mine-free cell, this cell is colored green…

By Daniel
( @DanielRapp, website )

Polygon packer

By Nick
( website )

A recreation of the Laughing Man from Ghost In the Shell

By Kyle Simpson
( @getify, website )

A #js1k script compressor, used on its own source code to get it to exactly 1024b!

By Simon Key

Conway's Game Of Life, the classic cellular automaton.

By Mr Speaker
( @mrspeaker, website )


By Frederic Cambus
( @fcambus, website )

A visual representation of a stripped-down bubble sort algorithm producing diagonal lines pattern. Total size : 323 bytes.

By Paul Brunt
( @super_eggbert, website )

Interactive 3D landscape, use mouse and keyboard to navigate

By Román Cortés
( @romancortes, website )

3D Text - Update for wrong code pasted

By razorwolf

A clone of the windows Mystify screensaver

By Phil McCarthy
( @phl, website )

Simple water simulation based on cellular automata. Move mouse to make ripples. Fast in latest Chrome and Opera, slow in Safari 5, almost inert in Firefox 3.6.

By p4p4
( website )


By Frederick Polgardy
( @polgfred, website )

Eliminate the blue pieces by clicking anywhere on the board. 8 : 50 isn't the time - it means you have 8 moves to clear all 50 pieces.

By Román Cortés
( @romancortes, website )

3D Text - Raycasting, accelerated by subsampling and a distance field.

By Hayato Araki
( @arahaya, website )

shooting game (trying to be) similar to the classic Asteroids.

By Frederick Polgardy
( @polgfred, website )

Clear away the blue squares by clicking anywhere on the board.

By GMChicken
( @GMChicken )

Random shape generator. Exactly 1KB!

By Noah Larsen
( @mental_x, website )

Randomly generates color boxes. Each click on canvas uses the x and y position to determine rgb color range of the boxes and background.

By GMChicken
( @GMChicken )

Random shape generator. 1K exactly.

By Martijn Hermans
( website )

A 3d water simulation based on an assignment i once had to optimize for a course.

By Rauri Rochford
( @raurir, website )

Bunch of cubes move in and out randomly.

By Zach Carter
( @zii, website )


By Remy Sharp
( @rem )

Allows you to run the Flash ActionScript tweetcoding demos that focused on graphics based demos - but on a canvas. Copy and paste examples from the follow url to see ActionScript render right before y…

By Christian Krebs
( @__chris__, website )

The flying carpet. A little contemplative recreational experiment with the RGB color cube.

By Yuri Ivatchkovitch
( @y3i12, website )

Colorful Wavy Waves.

By Rebecca
( @veubeke, website )


By Dustin Silverman

Initially an attempt to recreate Battlezone in javascript, then cut down to a simple first person engine to keep it under 1k.

By bradleymeck

Click on the @ to make it change speeds!

By nrkn
( @nrknthuk, website )

Maze-CAD program for villains. Design your maze then watch a simulated hero navigate it. Try to make your maze as long as possible, and after each round it will tell you the score for the last round a…

By NickyOne
( website )

Generate 600 divs and make simples ondulations...

By Joeri Sebrechts
( @joeri_s, website )

Side-scrolling fighter game. Arrow keys move, space fires. Second version now has more of a retro look (and fixes some bugs).

By Luhr Løvdahl

By Michal Hantl
( @michal_hantl, website )

It's raining cash

By sacah
( website )

Raycasting maze, use arrow keys, Up/Left/Right to move. Now with colors.

By nod
( website )

JS implementation of the one-led clock : http://www.opengpstracker.org/one-led-clock.html

By Paul Hammond
( @ph, website )

An implementation of the cellular automata Langton's Ant:

By Lindsay Evans
( @lindsayevans, website )

"If a million* monkeys^ sit at a million* pixels and randomly change them, they will eventually produce the Mona Lisa."

By TuringMachine

Machine in a machine - Turing Machine Implementation.

By ponce
( @p0unce, website )

Kaleidoscope, hypnoglow, feedback.

By Pavel Bakhilau

Pixel Painter game. Click on the colors at the bottom to 'fill' the top left pixel (and others like it) with that color. You have a limited number of moves to paint the entire board. It's very addicti…

By Dan Nye
( website )

An homage to the 8-bit Atari version of Boing (http://www.youtube.com/watch?v=bhBzmnH_fRQ).

By "Cowboy" Ben Alman
( @cowboy, website )

Organ1k, "An organic play of color that will hopefully keep you staring endlessly." Just sit back and watch or interact with the mouse! Read all about the concept and byte-saving techniques used at ht…

By Jonathan Brodsky
( @jonbro, website )

lookup table based displacement. borrows heavily from other prods here, got the lookup math here: http://openprocessing.org/visuals/?visualID=3624

By ChAdams
( @chlithadams )


By robofarm
( @robofarm )

Pixel duel.

By Livingston Samuel
( @delivi, website )

Creates a grid of squares that animates colors as the mouse moves.

By 0x00
( @0x00, website )

some sort of a cellular automata.

By Adam Antók
( website )

Sticker ABC. Drag the upper-left corner to reveal the next sticker.

By Christian Krebs
( @__cris__, website )

The flying carpet. A little contemplative recreational experiment with the RGB color cube.

By Alex Epifano
( @msm595 )

A 3d cloth simulation. Interact with it! Drag it! Fun!

By Dawid Kubiak
( @dawidkubiak, website )


By ewoudj
( @ewoudj )

Collection of old school effects (sinus scroller, raster lines, starfield, etc.). This marks my return to the demo scene after a 22 year hiatus. :D

By Jotamaza

A simple old-style PONG game. Pad size changes as you scores to level the game. Wins the first that gets without pad.

By GregT
( @panzeronline, website )

Rorating cube - small update. No scale/pulse and motion blur but fixed height and dynamic shadows

By proppy
( @proppy, website )

Ferris wheel, now with blue sky and clouds.

By Eneko Alonso
( @eneko, website )

The Sun

By Kyle Simpson
( @getify, website )

A web page screensaver, able to transparently overlay any page if a user leaves their computer idle for too long. Makes for a great easter-egg on an otherwise boring site.

By Pat Cullen
( @patcullen )

An interactive 8 Bit Adder.

By Bri Lance
( @yeah_its_me, website )

Two swarms of fireflies chase each other around. The same flocking algorithm is used on individual fireflies and on the swarms themselves.

By Roy F. Dvorak
( website )

Random Walk version 1.4. Generate a random number from 0 to .999999.

By Paul Brunt
( @super_eggbert, website )

3d particle system with text and reflections

By Chris Francis
( @chrisfrancis27, website )

"Formula 1K" - a racing simulation. Experience the adrenaline rush of sheer horse-power and blistering speed.

By Scott Ellis
( @sje397, website )

Draws a '3d fractal' using quaternions for rotation.

By Dean C. Forrest
( @iamneutek )

TB-303 Emulator, tweak the JSON, hit OK and your acid line will be rendered to an audio tag, turn up your volume and hit play :)

By Pedro Cardoso
( @pcardoso, website )

var desc;

By Nikhil Marathe
( @nikhilcutshort, website )

An implementation of Substrate (http://complexification.net/gallery/machines/substrate/)

By Garret Kelly
( @gkelly, website )

Animated unshaded raytracer. Renders an animated ring of spheres against a shaded background.

By codenamuser
( website )

Triangle fire, which follows the mouse....

( @pt_tr, website )

Sim Ci- I mean... CitySim1k!

By p4p4
( website )


By nrkn
( @nrknthuk, website )

Yellow vs. Red, a roguelike game. Movement with mouse. Enemies are red, health green, level exits black. Walls can be moved like sokoban. Gaining enough experience or clearing level gives you extra he…

By Michael Deal
( @mudcube, website )

Color-Vision Simulation & Daltonization for Protanopic Observers

By oberhamsi
( @oberhamsi )

Robot Warehouse

By Siver K. Volle
( website )

Throw a ball around with two rubberbands, one connected to the mouse cursor and the other to the ball in the center.

By tantetoni2
( website )

Backround color flasher, to change the background color move or click the mouse or use the scrollwheel.

By os0x
( @os0x, website )

pixel breakout! forked from http://wonderfl.net/c/tNGi

By Afshin
( @micronova, website )

Matrix background which warps around your mouse as it moves

By Scott Ellis
( @QOAL, website )

Smexy metaball (v2.1)

By Lee
( @leegao, website )

A simple text editor that automatically highlights Javascript code in the textarea as you type. (an edit-in-place sh)

By Sayan "Riju" Chakrabarti
( @sayanriju, website )

This script draws a TURMITE which is a Turing machine which has an orientation as well as a current state and a "tape" that consists of an infinite two-dimensional grid of cells.

By Eric McGraw

3D Chess setup. Pieces are draggable and drag on the board to rotate the view.

By Steve James

Conway's Game of Life.

By Mark Homans
( website )

3d effect on grid

By Peter Nitsch
( @peter_nitsch, website )

Twisty Sierpinski Gasket in 3D.

By Andy

A tiny particle system.

By Philip Wagner
( @houly, website )

Implemented the perlin noise algorithm. It's pretty big, so there wasn't much room left. But i love it so much. Click the canvas to generate a new seed.

By Mathias
( @mathias, website )

Color picker extraordinaire™. Move mouse, scroll and/or click to adjust the color. Also, try resizing the window!

By notcub
( @notcub )

Spins a pyramid, with blue->white additive compositing effect.

By Mikhail Davydov
( website )

Oldstyle pixel car game.

By ianh

Draw a groovy background pattern. Press 'u' to undo. [updated to make the undo feature suck less]

By Simon Jefford

Update to 353:

By Sam Birch
( website )

Infinite vines + flowers!

By Ben Larson
( website )

SquareRaid is a lunar lander type game... except instead of a lander, you're a square, and instead of landing, you're mercilessly carpet-bombing evil enemy squares, and instead of taking place on the…

By Zack Halbrecht
( @zackola, website )

Fuck yeah plasma fractal with cheap color cycling.

By Otto Bibartiu

Ambient background color changer (tweetable).

By Carl Cox

Mimics Apple's HTML5 Typography Demo.

By case
( @corpsmoderne, website )

"The Black Hole" - Particles+Gravity. The number of particles is dynamically adapted to the power of the host. Obviously prettier with lots of particles...

By kadir pekel
( @kadirpekel, website )

Simple fun game aka Same Game

By Giancarlo Bellido
( @giancarlo84, website )

Conway's Game of Life

By Patrick Denny
( @atomicnoggin, website )

Old school (circa 98) mouse trail in under 1/2 a K. Uses an object pool to minimize memory usage and HTML/CSS3 to create the trail. No canvas required. Update 2: Slightly smaller (tighter CSS footprin…

By Jakub Łopuszański
( website )

3D engine with bones and animation without canvas.

By William Malone
( @williammalone, website )

I gave JavaScript objects an identity. They are flies. They live; they reproduce; they die. Sit back and watch them evolve based on the rules of their world, or take a more active role in their evolut…

By Hans Schmucker
( @Schmucker, website )

A very simple synthesizer playing "The Drunken Sailor". This is not so much a demo as it is a component for other demos. It is not minified, except at the most basic levels and the notes notation isn'…

By Marijn Haverbeke
( @marijnjh, website )

Deep Space Defense (version 3)

By Tons of Particles
( @y3i12, website )

50k particles moving according to their own positions.

By cartuchogl
( @cartuchogl, website )


By Oscar Nevarez Leal
( @insan3, website )

Hilbert Curve Implementation

By quoj
( website )

Fireworm: Eye candy with the gradient drawing tools of the canvas tag (no direct image writing) and a little bitmapped logo coded into 30 characters of ASCII (6 pixels a char, eh!) And thanks to Peter…

By Roger Willian

Maldelbrot fractal viewer. Double click to zoom in, right click to zoom out.

By James Padolsey
( @padolsey, website )

Urm. It's a digital clock.

By roylory
( website )

Javascript minifier. It uses the same algorithm as jsmin by Douglas Crockford.

By Michael

Just a simple star field, but with a bit of a twist.

By Brian Long
( @newobject, website )

"The Legend of Ecma." Descend the dungeon to find the amulet of Ecma and then return it to the top floor. Monsters subtract 1 health, potions add 1 health. Features: 1 bit pixel art, randomized dungeo…

By Mark Tucker
( @tuckermark, website )

A game: you have one click to start a chain reaction to destroy all the balls.

By Tim Beyer
( @mrmooh )

Creates random animated Spirograph patterns

By profil
( website )

Move your mouse and circles will pop up!

By Ilkka Oksanen
( @ilkkao, website )

Simple game. Click mouse to create a new vessel.

By shannon
( @ShannonBarratt, website )

Breakout Game (update)

By Andreas Gustafsson
( website )

Zooming and rotating chessboard in 255 bytes.

By Rubén Medellín
( @chubas, website )

Frost simulation.

By Christopher Pitt
( @verylastminute, website )

Provides a function to generate and animate a spinner. You can customize the following options:

By Barry van Oudtshoorn
( website )

A re-implementation of http://www.barryvan.com.au/demos/swarms/swarms.html, which in turn is a reimplementation of a Processing script that I wrote. :)

By ryan
( @mistabell, website )

twitter-friendly sunburst

By Thomas Braun
( @zwitschertom, website )

The popular Hacky Sack game for the browser. Just click the ball to make it jumping around. Colour your life ;-)

By Greg Reimer
( website )

PHIreworks! version 1.2 (keep reloading to see variations) (find the easter egg)

By Michael Bolin
( @bolinfest, website )

Connect 4. Input is with the number keys.

By George Calm
( @georgecalm, website )

Uber Binary Clock.

By Erryn Pollock
( website )

A random terrain generator with a Linear Congruential Generator to generate pseudo-random numbers that give a bit more organic result.

By Abram
( @abramh, website )

A game of board domination, grow your creep larger than the enemy AI's creep.

By Egon Elbre
( @egonelbre, website )

Flock of birds.

By John Drake
( @f0x0x, website )

Just another Matrix display, but a bit more true-to-form than the others I see here already. Glyphs are hiragana, katakana, and maybe some other junk.

By Inopia/Aardbei

Recursive radial blur.

By Alex Michael
( website )

Smalls avoid bigs, bigs eat smalls. Life as it happens to be. You can even bet on it.

By Ross Cairns
( @rossc1, website )

Cylindrical Graphic-ism.

By Roland Bouman
( @rolandbouman, website )

An interactive Query tool for the Web SQL DB API (see http://dev.w3.org/html5/webdatabase/)

By Benoit Côté-Jodoin
( @becojo, website )

Simple retro text. I modified the size so the performance are better.

By Mauro Lizaur
( @paqreligion, website )

A *very* basic japanese IME (input method editor) which automatically converts romaji to Katakana (by default) or Hiragana.

By Ryan
( @mistabell, website )

circle meets square

By Peter Nitsch
( @peter_nitsch, website )

3D Lorenz attractor with an oscillating Prandtl number. Rotation adjustable by mouse movement.

By Rüdiger Appel
( website )

Improved Railway Station Clock

By Anthony Bowyer-Lowe
( @yoknapatawpha, website )

Tweetable (130 bytes) approximate calculation of Pi with random numbers.

By Chris Francis
( @chrisfrancis27, website )

A simple ever-changing, multi-coloured fence disappearing into the distance. Fits in a tweet, complete with #JS1K hashtag!

By mfirdaus
( @mfirdaus, website )

Tower of Hanoi. Interactive. Move the disks from the left rod to the right. Bigger disks can't be placed on smaller ones.

By Sam Stephenson
( @sstephenson, website )

Color Tetris in 1024 bytes of JavaScript. Hand-packed. No funny bit-shifting operations.

By P. Envall
( @npup, website )

** Updates:

By Román Cortés
( @romancortes, website )

3D Snowman

By Dominic Szablewski
( @phoboslab, website )

Some bugfixes on my Syntax Higlighting Quine. Also killed a few bytes but added a lengthy comment in turn.

By Hans Schmucker
( @Schmucker, website )

Update: Adds Opera compatibility by replacing location.search parsing with parent.variable for counting. See previous entry for description.

By Matthias Reuter
( @gweax, website )

In a tweet: Randomly colorizes the elements of a page. Unfortunately, the demo page only has three visible elements. Ver.2, down to 120b)

By Cay
( @Cay, website )

Very simple perlin noise-based flocking behaviour. (Updated)

By Martin Kleppe
( @aemkei, website )

Lorenz Attractor

By Joachim Viide
( @jviide, website )

An elastic twister effect.

By Keith
( website )

Simple circle animation

By Michael Deal
( website )

[1.1: fix drawing bug, improve rendering]

By Daniel
( @DanielRapp, website )

Polygon Packer

By John Lyon
( @jozzas )

Pretty simple plasma zoomer

By Ivan Zhekov
( website )

Implement upcoming pair of elements

By Carl

Script paints the screen from a circular 'window' into the next color.

By Andreas Köberle
( @eskimobloood, website )

Version 2 of the Guilloche Pattern generator, now with some sliders (or simple inputs, sorry ff).

By Michal Hantl
( @michal_hantl, website )

Matrix has you ...

By Stefan Franke
( @stefanfranke, website )

Conway's Game of Life

By fearphage
( @fearphage, website )

This is a basic implementation of Conway's Game of Life that is a representation of cell automation.

By Tom Boshoven
( website )

Conway's Game of Life!

By Karsithe
( @karsithe, website )

The script renders a 2d image of a road running through a desert. It's dumb, but it does fit in a tweet...

By Jan Kasper Martinsen

sinus scroller

By Cay
( @Cay, website )

Very simple perlin noise-based flocking behaviour.

By BudniX
( website )

The beauty of symmetry

By Mark Talbot
( @thesandbag, website )

IFS fractal fern

By Ryan
( @mistabell, website )

isometric level-3 menger sponge

By Kevin Roast
( @kevinroast, website )

Updated version of the Warp Starfield demo. Tracks the mouse to modify the direction of the warp field, plus you can use the mouse scroll-wheel to control warp speed!

By Mathieu Davy
( @ekynoxe, website )

Mastermind: Guess by submitting 4 digits from 0-9.

By Steven Wittens
( @unconed, website )

Pulsing 3d wires with volumetric beams.

By Sean Cline
( @majincline, website )

Conway's Game of Life! Mouse interacts with the canvas. Clicks toggle between "fading" and "classic" mode. Full version available here: http://www.eng.utoledo.edu/~scline/life/life.html

By Per-Olov Jernberg
( @possan, website )

Classic raytraced tunnel, now works on Opera

By John Turknett
( website )

Classic Simon type match game. Click "New Game" watch the colors, click the same pattern once it has stopped. See how far you can get.

By Sam Birch
( website )

Infinite vines.

By Will Scott
( @willscott, website )

Generate and explore a random maze. Creation uses Prim's algorithm and exploration implements a simple wall follower.

By Alexey Malyshev
( @alexeym, website )

True binary clock. Shows number of milliseconds since Jan 01 1970. Fits in a tweet.

By Mauro
( @paqreligion, website )

Just the 'awesome face'. awesome indeed.

By z0va
( @z0va, website )

Subliminal demo.

By Dan Steinman
( @jaxcore, website )

An exquisite mustache with background music (requires quicktime)

By Mike McNally
( @m5, website )

Minesweeper game - if you win, the mines are drawn in green. If you lose, you explode.

By Patrick Wied
( website )

This 1k app generates a realtime heatmap depending on the user's mouse movement (default map size is 999x500)

By Michal Hantl
( @michal_hantl, website )

Poke around with mouse to find gray hair.

By Vincent Schüßler
( @_Vincent, website )

Draws a simple, color-changing "wave".

By Graham Bradley
( @kissmyawesome, website )

Conway's Game Of Life (http://en.wikipedia.org/wiki/Conway%27s_Game_of_Life) in precisely 1Kb.

By alteredqualia
( website )

Bubbles and worms. Two demos in one for more fun.

By Derek Hammer
( @hammerdr, website )

Just a short 'video' of some sort of space flight. I'm not really sure and was just playing around :)

By Hans Schmucker
( @Schmucker, website )

A little romantic waterfall in a nostalgic color palette. In other words: Random ASCII blocks scrolling down. Not exactly 140 bytes in utf-8, but still 140 characters (Twitter accepts it).

By Tane Piper
( @tanepiper, website )

Generates procedural water ripple effects on top of a randomly generated gradient background.

By William Cotton
( @williamcotton, website )

Feedback Loop.

By Motyar
( @motyar, website )

The "Minimalist todo list" can be used as a task manager, simply type your task and press Enter to add task. To remove task simply hover the task and click.

By Martijn Laarman
( @Mpdreamz, website )

A simple animated naval ensign of Japan.

By Robin Allen
( website )


By Maarten Decat
( @maartendecat, website )

A 1K version of the all-famous Flash game Bubble Trouble (Google it!). Move the mouse to move, press left mouse button to fire, don't get hit by a ball and try to destroy all the balls.

By Astrlndr
( @th3sturd, website )

Retro Astro Lander clone (well, that's what it was called on Timesplitters 2!). Use the space bar to keep the rocket from accelerating into the terrain. Keys A and D rotate the rocket to allow side…

By Sergey Chikuyonok
( @chikuyonok, website )

JavaScript implementation of the "classic" water ripple demo. Move mouse pointer over the image to get more ripples.

By Georg Tavonius
( @Georg_Tavonius, website )

Minimalistic flying game. Use cursors to control the plane.

By 29a
( @29a_ch, website )

A demonstration of evolution by natural selection in 999b. View the source, it's pretty. Visit 29a.ch for more details.

By Carl Jackson
( website )

Draws pretty snake-like things

By MichalBe
( @michalbe, website )

Simple side-scrolled space game. Control spaceship with your mouse and try to avoid pink rects. I made first version of that game in almost 1,7kb and it looks much better nicer, try it here: http://no…

By Hans Schmucker
( @Schmucker, website )

A strangely growing mountain in Twitter-friendly 140 characters.

By Nick Lockwood
( website )

A simple random maze generator, using the Recursive Division method described on Wikipedia. The code was hand-tuned for size (which mostly involved extracting common sub-expressions and removing edge-…

By Christian Neukirchen
( @chneukirchen, website )

Munching squares in twitterable size

By Simon Madine
( @thingsinjars, website )

(Probably) final update - now with Blur. Pretty spinning circles that chase the mouse (or finger) around. Click (or tap) to add more circles, press any key to toggle blur on and off. Blur also toggles…

By Ronald Jett
( @rjett, website )

N-Body simulation using canvas.

By sq2
( @raurir, website )

Connected meandering dots

By Kris Cieslak
( @kcieslak, website )

Arkanoid/Breakout game. Use left/right arrow keys to move the platform, F5 - new game. Only one level (It's only a demo).

By guciek
( @kguciek, website )

Plasmodrops. They drop.

By Michael McDaid
( @mcdaid_, website )

A 3D chequered tunnel like effect. Use mouse to create different effects, x axis changes rotations speed, y axis changes how quickly image fades away. Click the canvas removes a square/arc, making the…

By Christophe Résigné
( @chiptune, website )

a plasma!

By Kasper J. Jeppesen
( @kasperjj, website )

Multicolored voxel moonscape.

By Michael Deal
( website )

An RGB color spectrum mixer, controlled by your mouse movements. Move left to turn up red, right to turn up green, and down to turn up blue. Great for music visualization, become your own lighting D…

By Andreas Köberle
( @eskimobloood, website )

Simple Perlin Noise implementation on canvas. Its very slow on firefox but it runs.

By Anthony Mann
( @mrnibbles, website )

Plasma effect, click to randomise.

By mi-ku
( @mi_kudev, website )

Scrolling checkerboard with text on animated gradient background.

By Yoeran
( @yoeran, website )

Just playing with Brownian motion.

By Charleston Waltnikki
( website )

Computes pi in a non-optimal fashion.

By Thomas Fuchs
( @thomasfuchs, website )

A tweet-length JavaScript quine (a program that outputs it source). As I'm a juror, this is for the showcase. :)

By devfuture
( @devfuture, website )

Just music visualization. Equalizer.

By Jon Gjengset
( @jonhoo, website )

Dynamically draws a background pattern using several traced paths

By lintaba
( @lintaba, website )

Just a sphere, that you can rotate with the mouse :D

By Dan Steinman
( @jaxcore, website )

Hypnotic spinning star simulation, random stars each reload

By Miller Medeiros
( @millermedeiros, website )

Predator on acid.

By Luis Gonzalez
( @luis2048, website )

rotating 3D wireframe cube + oldschool fire effect

By Trevor Norris
( website )

Meant to be used with client-side graphing/analysis tools, as a more dynamic means of rendering graphical reports and charts.

By Mikael Roos
( @livedo, website )

A metronome with an audible tick and configurable BPM. Audio does not work in Chrome (lacks support of wav, huh), so I'm considering it an extra feature. ;)

By Mathias
( @mathias, website )

Let’s just say I called it “ἐπιληψία”.

By Johannes Fahrenkrug
( @jfahrenkrug, website )

Poor Man's ASCII Art generator: draw on a canvas on the left, behold the ASCII art on the right. Reload to start over.

By Paulo Falcao
( @PauloFalcao, website )

RGB feedback effect, use your mouse to change parameters.

By antimatter15
( @antimatter15, website )

3d function plotter. fixed and works in ch, fx, op

By Anthony Bowyer-Lowe
( @yoknapatawpha, website )

Updated marching moire XOR madness in 333 bytes.

By QuintenC
( @qubecity, website )

*update: less randomly broken line in 3d that rotates on mousemove

By antimatter15
( @antimatter15, website )

3d function plotter

By Matt Hobbs
( @1manSaint, website )

Updated - Coloured particles bouncing around the screen. Colour of the particle changes depending on it's proximity to the 3 coloured points.

By Mathieu 'p01' Henri
( @p01, website )

There can be no size compo without a Quaternion Julia raymarcher ( using Hubbard-Douady distance estimator )

By Malte Ubl
( @cramforce, website )

Don't let Mario run against the lines! (Use arrow up to jump)

By antimatter15
( @antimatter15, website )

Updated version of gravity submission. Click to add a dot, the size is determined by amount of time the mouse was down, position is determined by where you click and initial velocity is the distance f…

By Andreas Köberle
( @eskimobloood, website )

Guilloché Pattern Generator

By Mr.doob
( @mrdoob, website )

(update) Reduced 50bytes thanks to Closure Compiler (http://closure-compiler.appspot.com/home) and some optimisations by @millermedeiros

By Christopher Otto
( @crassauto, website )

Time As Color shows the current time as color by setting red to the hour, green to the minute, and blue to the second. I originally created it in 2000 and it was shown at Gasworks London, Boston Unive…

By Tom Hudson
( @tomnomnom, website )

It's a fancy dancy clock. The innermost, thickest, hand is the hour hand. Attached to the end of the hour hand is the minute hand, and the second hand is attached to the end of that.

Crazy multiplayer 2-sided pong

By feiss
( @feiss, website )

*Crazy multiplayer 2-sided pong*

By Galchwyn
( @galchwyn, website )

This demo tries to emulate a pulsar star. It shines and fades within a period of 2 seconds, approx., and changes its direction when it touches any side (a classic).

By Remco Veldkamp
( @remcoder, website )

retro oldskool psychedelic disco effect.. just add beats ;-)

By Fedor Indutny
( @indutny, website )

Another one fractal painting script.

By Jim Lawless
( @lawlessGuy, website )

This demo displays 100 strings with the value "JavaScript" in random locations of an 800x600 rectangle. The font-family, size, and color are also randomized.

By Todi
( @tditlu, website )

Plasma light-polar coordinates-strange effect...

By Amrish Kapoor
( @amrishk, website )

Tweetable test for a web page's accessibility. It finds all the images with a missing 'alt' attribute and highlights each one of them with a thick red border.

By Amrish Kapoor
( @amrishk, website )

2 player Tic-Tac-Toe game

By Hakim El Hattab
( @hakimel, website )

Colorful particles follow the mouse and leave a smooth, fading, trail.

By antimatter15
( @antimatter15, website )

A clone of @rem's letter slinger that's under 1k in SVG.

By Marijn Haverbeke
( @marijnjh, website )

Draws a Pythagoras tree on the provided canvas (in 0xFF bytes)

By Marcin Ignac
( @marcinignac, website )

There is no demo compo without a wobbling tunnel!

By Fedor Indutny
( @indutny, website )

This is mini-version of jsTPL template engine.

By Ken Snyder
( @tr0gd0rr, website )

Detects and reports on whether your browser supports each of 42 features found in HTML5 and ECMAScript 5 standards.

By Andris Reinman
( @andris9, website )

Classic snake game. Use keyboard arrows to turn the snake. If you hit anything (the walls, the tail of the snake) then the game finishes. Eating brown dots makes the snake to grow longer.

By Ken Snyder
( @tr0gd0rr, website )

Charmap for HTML, listing characters by their hex entity. Great for finding and testing which symbols work in all browsers.

By antimatter15
( @antimatter15, website )

A simulation of gravity. Click anywhere to add dots.

By Marko Mrdjenovic
( @friedcell, website )

Lovely typographic fireworks

By antimatter15
( @antimatter15, website )

XMLHttpRequest GET, and POST working in IE since 6.0 and every other major browser in 266 bytes.