The object of this competition is to create a cool JavaScript "application" no larger than 1k. Starting out as a joke, the first version ended with a serious amount of submissions, prizes and quality.

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Check out demos from previous editions too! 2010, 2011, 2012

Flower Warfare
By Teddy Cross
( website, @tkazec )

Synth Sphere
By Noah Weninger
( @gleurop )
An experimental music synthesizer with real time FFT. To play a custom song, add a hash (#) character to the url and put the algorithm afterwards. All songs you play are saved to l... more

Plasma Flowers
By Josep del Rio
( website, @joseprio )
This graphical demo will show plasma with a kaleidoscope effect, which sometimes produces flower shapes; click on the image to randomize the plasma generation.

Moth Goo
By Anders Thøgersen
( website, @aklt00 )
You are a moth flying through the night eating the tasty nectar from the flowers and avoiding bumping into things. Use Mouse to navigate and spacebar to eat nectar from a flower

Strange crystals II
By Philippe Deschaseaux
( website, @ehouais )
The crystals have disappeared in the space/time fracture, but shiny Furbee has survived and is now accompanying the visitors. This is a humble tribute to @romancortes and @p01.

Repulsion playground
By Carlo Cannas
The red ball is pushed away from black nodes, add new nodes by dragging from an existent node, to delete a node shift-click it and add a fixed node with ctrl-click.

By André Röhrig
An Intro inspired by an famous Agent

Spring Pond
By Matt Krutar
My first attempt at creating a little ecosystem in JavaScript. What's it do? The blobs eat the globs. Then they split once they are full.

A Garden in Spring
By Steve Taylor
( website, @gostay )
A changing view of a garden and its inhabitants. Wait a few seconds for the inhabitants to show up...

Spring grass
By Vincent Guerin
Drawing grass with tendrils algo...

JS Console
By Tom Boshoven
A JavaScript console which seems to have taken quite a beating. Compressed manually and then crushed.

In Bloom
By Tim Smith
New life bursts forth, heralding spring's arrival! Inspired by the fantastic Assembly 2004 Invite by Moppi:

Over The Hills
By Joshua Koo
( website, @blurspline )
I imagine Spring to be a beautiful season that you don't mind spending your time in the hills, enjoying the beautiful blue skies and clouds. Here's my first js1k entry & gam... more

Sea Battle
By Oleksii Okhrymenko
It's slightly modified version of popular game "Sea Battle". Just click on enemy territory. F5 to restart game.

One Color Always Wins
By Kenny Gow
( @FatSaltButter )
Random vote algorithm benchmark. Reload for new set of random colors. Click to slow, click again to resume full speed. Double click to switch to high-res "paint-like&... more

Flower Power
By Manel Villar
( website, @galchwyn )
When Spring starts, flowers of all colours appear in the field

Catalan Nyan
By Raimon Ràfols
( website, @rrafols )
A Catalan flag waving + a star doing the ;)

Anaglyph Pong
By Aurélio A. Heckert
( website, @aurium )
Put your red+cyan glasses and play pong as you should do inside 1k TRON world. Your mouse is your racket. CAUTION! Game addiction will ruin your life, steal your tv and kill your goldfish.

First rays of spring
By Vincent Schüßler
( @_Vincent )
A simple live raytracer with reflections and shadows and stuff. Runs relatively smooth in Chrome, but is pretty slow in Firefox and Opera. Compressed by the Google Closure Compile... more

very strange attractors
By chris mckenzie
( website, @emorobot )
A system of 3 equations - doing quite a bit.

Playing in a Puddle
By Erik Skau
A puddle rippling and playing music as raindrops fall. You can also play in the puddle by clicking and dragging through it. The notes work sort of like a theremin; volume varie... more

Fractal Typography
By Adis Hamzić
( website, @hamzadis )
The Spring unwinds and Summer comes forth, rejoice! But better get a cup of coffee first, this might take a while... This is a Julia set renderer with a point and bitmap orbit tra... more

Spring (on paper)
By Adam Wentz

Partically Good
By Christopher Eaton
( website )
Small circles explode from your mouse position and can be flung out by holding then releasing your mouse button. The more circles on the screen, the larger they get. All circles bounce off the edges.

Javascript Dreams
By Will Ridgers
( website, @wridgers )
Renders fractal flames similar to electric sheep. Users can make their own and share them.

You Are Here
By Oakley Jurgens
( website )
Displays the browser's location on a spinning globe. Written quickly, then beaten with a stick for days until it was small enough. Then discovered that JSCrunch gives me 100 more bytes...

Underground Chamber
By Timothy Volp
A dark, cold, underground chamber deep below the surface of the earth. Use the arrow keys to walk forward/turn but try to avoid walls, they are not solid. Credit to aivopass for JSCrush!

Text growth
By grgrdvrt
( website, @grgrdvrt )
Type, press enter and let Mother Nature do the job

Daisy Chain
By Yann 'Aaunel' Eves-Hollis
( website, @aaunel )
Generates a random chain of blooming daisies!

By Tom Hargreaves
( website )
Plays a tune

3013 The 䕵 space-time fracture
By Mathieu 'p01' Henri
( website, @p01 )
The miners were right! Damn Furbee came close to the strange crystals and opened a space-time fracture 1K springs into the future, trapping a 䕵 Mech inside a time bubble. * * * ... more

Picross/Nonogram/Hanjie Puzzle in 1K of JS. Allows you to create, share, and play puzzles that can be stored in a URL parameter. For example, try pasting this onto the end of the... more

By Yang Bin Kwok
It doesn't need to warm up! Written while waiting for mine to warm up... Refresh for new blobs! Will attempt to fit browser height on load.

By Evan Hahn
( website, @EvanHahn )
Draw colorful circles!

By Eric V. Garcia
It's Spring, so let's play a simple game of mini-golf. Click on the play area to move the golf ball in that direction. Get the ball in the hole and the flag will display how many ... more

Julia Fractal Browser
By Doug Haber
( website, @LeshyLabs )
A Julia Fractal Browser with Stripe Average Coloring. Controls: * Use the mouse wheel to zoom in and out. * Press the "Next" button to cycle through available frac... more

NOT Logic
By Alex Patton
( @alexpatton63 )
A logic simulator inspired by Minecraft's "redstone" mechanics. Click on the grid to place a component. Press any key to switch component type. 3 components are included:... more

By Benjamin Bill Planche
( website, @b_aldream )
Pointillist representation of an animated landscape: watch Spring comes and passes, and moving shadows casted by clouds. ===Controls=== - Move the mouse to fly around. - Drag ... more

1024 byte sequencer
By Per-Olov Jernberg
( website, @possan )
Expression based webaudio sequencer and sampler

Spring source
By Małgorzata Jatczyk
( website, @dcwebdev20 )
Simple colourful bokehs.

1K Meteors
By Oscar Toledo G.
( website, @nanochess )
Pilot your ship through space and remove meteors from field. Rotate with left and right arrows, advance with up arrow, shoot with spacebar. Caveat with aliens lurking. If you... more

Nigh and day
By Damien Fayol
( website )
A short attempt at making a spring-ish scenery.

Rainbow Grid
By Joshua Wright
springy rainbow grid

Mossy Text
By Will Scott
( website, @willscott )
The undergrowth will eventually reclaim your intrusions.

the chase
By Eric Basti
( website )
A very simple example of basic attraction, and some canvas fun. Nothing too extreme. Works with a mouse and on (most?) touch devices.

By Jon Carroll
Any key makes a new random maze, UP also zooms in DOWN zooms out (more compexity) - max zoom at 2x2 pixel tile size, will also resize itself to fit the screen. Inspired by Neil Fr... more

Springy Blobs
By Grant Kot
( website, @kotsoft )
Attract nearby blobs by moving the mouse. Simulates several hundred blobs, collisions between them, and collisions with a sinusoidal terrain.

1Keyboard 100Friends
By Pyrofoux
( website, @Pyrofoux )
A game with one keyboard for 100+ players ! Each has a key and the only who press earns points.

By Sventuba
Start by pressing 's'. The big dot is you, the small dots are zombies. You run using arrow keys and you try to stay alive. "Run" in swedish is "spring", so the ... more

By Arthur Gunn
( website )
It's interactive! Move the mouse to draw new shapes, click to change modes. Can visualise music if your browser supports it! Enable "Web Audio Input" at chrome://flags/

Bouncing Balls
By Curran
( website, @currankelleher )
Circles bouncing around and colliding. Click and drag to attract them to your mouse. Learn how it was coded at

Game of Life
By Daniel Bali
( @balidani )
Simple Conway's Game of Life implementation - Click anywhere to add a cell - Press any button to stop/start the simulation

By Derek Ries
( website, @derek_ries )
Control the blue arrow and pick up as many blue coins as you can. But be careful to avoid the red guys! Use the W,A,and D keys to steer.

By haengebruegge
( website, @haengebruegge )
Your are the spring Sun, the yellow square on the bottom. The blue square is your enemy, the winter with his troops. Destroy as much as you can! Shoot them with the space key... more

Super Mini Hexagon
By feiss
( website, @feiss )
Fully playable Super Hexagon clone ( How to play: 1: Put some trance/house/goa music at top volume 2: Use your arrows to move the small triangle and a... more

By James Allardice
( website, @james_allardice )
Springy is a simple Doodle Jump clone. Move your mouse to the left or right to control your spring and see how high you can jump! Now featuring mobile accelerometer support!

Black Dots
By dotfury
( website, @dotfury )
Move the mouse around to add balls to the screen, clicking on the mouse changes to spread out mode, you can add balls to the screen in this mode too. Click the mouse to switch between modes.

Shoot mmm'k
By Bradley Meck
( @bradleymeck )
A simple shoot em up game. Arrow keys to move Space to shoot Grab upgrades before they disappear

A live anime-like picture: have you ever tried to catch a firefly?
By Carlos Reventlov
( website, @xiam )
It's just a peaceful anime-like live picture. I wanted to make something beautiful, with nice graphics that would work on powerful and low-end computers with Chrome, Firefox or Ope... more

Furbee, get out of that tunnel ASAP!
By Roman Cortes
( website, @romancortes )
This is a tribute to amazing Strange Crystals by @ehouais ( As my original Furbee entry ( and ehouais' ... more

Winter Wrap Up
By Arne
( website, @veubeke )
Before spring can start winter has to be cleaned up. It's your job to move the remaining snow piles to spots of grass that have died during winter. Inspired by the MLP:FiM episode... more

Strange crystals
By Philippe Deschaseaux
( website, @ehouais )
"The miners have stopped working. They are afraid. It all seems to come from those strange crystals that some have seen." Be patient and with a bit of luck, you'll see... more

By Alexis Jacomy
( @jacomyal )
SprinGoo is a 2d playground inspired by World of Goo, where you can build structures made of balls connected by spring-like connections. CONTROLS * [p]: Increases mouse action... more

April showers bring May flowers
By Abigail Cabunoc
( website, @abbycabs )
Use your typing skills to turn April showers into May flowers! Create as many flowers as you can. The more you create, the faster the rainfall. Don't let the rain reach the ground ... more

Oldskool Plasma
By Juhani Imberg
( website )
Oldskool plasma effect in all of its glory.

3D City Tour
By Jani Ylikangas
( website )
1st person view of a springtime island city. Use your mouse to fly over the city, jump from roof to roof or drive with the cars on the streets. You can also just let the autopilot ... more

ConWAY of war
By | / ◕‿‿◕ |ᕁ/
( website )
A simple three-colored game of Life. Three differently-shaded lifeforms strive to survive on looped field. Click to restart. Right click to switch to RGB color scheme and back.

By Roman Cortes
( website, @romancortes )
Spring bee with springy antennae and my trademark tie from my logo/website. In this entry I'm pushing the limits of what is possible with 2d canvas and high-end hardware. To ful... more

By Siorki
( website, @Siorki )
Helicopter simulation, tribute to the game Comanche : Maximum Overkill. Use arrows to control pitch and roll. Altitude is on autopilot so no matter how hard you try, you cannot ... more

By Arct1k
It says it with flowers

Don't worry, bee happy!
By Manuel Rülke
( website, @homecoded )
After a long hard winter our little busy bee wakes up and happily flies off to check out the awesome tasty flowers. And it thinks ... "I love the smell of utf-8 flowers in the... more

By Benjamin Bill Planche
( website, @b_aldream )
"They said I could be anything..." - 3D Mesh ===Controls=== - Change the camera orientation with the mouse. - Click to generate an impulse, briefly affecting the mes... more

Mars Rover
By Ashley Bryant
( website, @ashesid )
Take a tour over a randomly generated 3D map. Includes shading by height and distance and cropped to a circular radius. Had to trim a lot of code so there will be the odd artif... more

By Cheeseum
( @chisumu )
A colorful, blooming, polar (as in graph) flower.

A Penrose by any other name
By Daniel Lauzon
( website )
With 5 dimensions this yields a Penrose Tiling; a 5-fold symmetric non-periodic tiling of the plane. Rich geometric subject, and beautiful tiling. squeezing it into 1k - price... more

Matrix style Conway's Game of Life
By Asafh
( website, @asafhd )
Runs a Conway's Game of Life simulation in matrix style, containing a "Gosper glider gun". Hovering over canvas revives cells

Rainbow Tunnel
By Andres V
( website, @KaeruCT )
High-speed rainbow worm hole, move your mouse to change perspective, scroll to change speed, click to pause/unpause

Psychedelic animation
By Piotr Stosur
Animated fractal shapes(mainly rotating spirals) similar to CEVs after taking psychedelic/dissociative drugs. :P Based on copying previous frame into 4 smaller fragments(once per f... more

Water Spring
By Asad Memon
( website )
DIRECTIONS: Move your mouse around to create fluid particles on left side of the screen. Spring Water, tasteless, odorless, colorless but valuable and versatile. A full impl... more

☺ Puzzle
By Mikhail Davydov
( website, @azproduction )
←↓→ & try to collect all ☺!

By Alex Turpin
( website, @AlexandreTurpin )
Remake of Tron's light cycles game. Left and right arrow key to control blue player. Don't hit the walls or another player.

The Little Engine
By Emory Hufbauer
The Little Engine that Could (fit into 1k). That's right, a little physics engine in 1024 bytes. It will work in any browser, but is fastest in Chrome. Click to fire a beam of obje... more

Math Graphs
By Mohsen Azimi
( website, @mohsen____ )
t draw 2d mathematical function. It has pan and zoom functionality. Functions can be complex and include sin, cos, tan, cot and power.

Spring Landcape
By Frederic Poeydomenge
( website, @pulsar64 )
Parallax scrolling of multiple repeating background layers composited on a single canvas : Starfield, Fractal mountains, and IFS trees.

Spring is in the box.
By Anders Corlin
( @esotericFX )
Boxes and scrolling text. Second effect showing after 10s. Source is minimized but not compressed. No evals and shit.

One more kilobyte
By Inopia
Flat shaded metaballs using marching tetrahedrons. Use Chrome for best results.

tiny solar system
By Marco Pro Campos
( website, @marcospc69 )
tiny solar system It all starts with a star and a planet. You can create more planets by clicking with the mouse and wait to see how it behaves.

Treasure Quest
By Philip Wagner
( website, @houly )
An exciting dungeon crawler. Features: * Awesome Graphics! * Maze generation à la Prim * Evil Enemies * Collectable Treasures * Permadeath Move with arrow keys. If a... more

Stick JS
By Damian Cipolat
( website, @DamCipolat )
This script lets you animate a stick figue by json, movements that can be achieved are similar to those of a human, as sequential movements avoiding robot. I recommend that you ... more

Simple Sequencer
By Arne
( website, @veubeke )
It's a simple sequencer with relatively clean and readable code though I had to sacrifice all whitespace except for the indentation. The point is to show that you don't have to gar... more

By Elias Schütt
( website, @elias94xx )
My third and final submission. :) Memorize the path and track it blind! --- The level generator is not the best, but the best I could do in 1024 bytes. Compressed with jscrush. <3

Animated 3D SIRD Plasma
By Philipp Stucki
( website, @_phst )
Animated 3D plasma rendered using a single image random dot stereogram (SIRD). Read on how to view a SIRD. Keys: ... more

Tunnel Racer
By Pim Linders
( website, @pimlinders )
Find your way through the winding tunnel -- but don't hit the wall! Use the left/right arrow keys or A/D keys to move the race car left and right

Simple Piano Recorder
By JiminP
Press keys(ZSXDCVG.. and Q2W3ER5...) to play the piano. Press shift key and press keys to make sounds one octave higher. Press spacebar to "snapshot" what you played. Y... more

Black Hole
By David Uselmann
Creates 99 stars that orbit a black hole using Newtonian physics. Up and Down key change time while left and right key control zoom. Careful, to fast increase iterative error.

swirled tree
By lacemaker
( website )
just another randomly generated pythagoras tree

Falling Letters
By Imran Latif
( website, @ilatif_bwp )
Press falling letters to score points and to test your typing speed ;-).

Simple Clocks
By Marek

Pac-Man in the park
By Krisztián Tóth
( website )
Who does not know the original Pac-Man game? Now, Pac-Man breaking out of the dark gloomy maze, and came out for a walk in the park in spring. Features: - Pac-Man game. Spring... more

By bga_
( @bga_ )
bit hard xonix, fitted into 1k = you is a spilder, can put web that fill bounding area if nobody inner = enemies * fly - act as bouncing ball, kill you if touch your web du... more

Drop The Ball
By Steven Scott
( website )
Drop the ball game. Use the left & right cursor keys to keep up with the ledges. Compressed with JS-Crush.

By Tamas Kalman
( website, @dh2k )
A classic demo scene plasma effect using floating point operations.

The Game Of Go
By Ben
( website, @shobute )
An implementation of the game of go (also known as baduk or weiqi). Has full rules including ko.

Lonely Planet Lander
By Alex Cruikshank
( @sivoh )
The goal is to land softly on the little planet. Arrow keys to rotate, space to thrust. You begin in orbit. You must determine your orbit and decelerate out of it in order to begin... more

By Robert Elek
Oldschool demo experiment, the classic rotating checkerboard with a few twists. Quite CPU hungry, i7 and Chrome recommended.

Tree Ninja
By Lars
Spring has come and tree structures are sprouting. Try your hand as a gardener by trimming them down!

Pachelbel canon in D
By Saturnyn
( @Saturnyn )
Plays the Pachelbel canon in D while displaying a springy/rainbowy animation. Sounds are generated using code from: http:/... more

Living Code
By Elias Schütt
( website, @elias94xx )
Outputs the code itself in a fancy way.

Stereogram Generator
By Dennis Koliris
( website )
A concise Stereogram Generator based on user input. If you don't know how to see the hidden 3D picture in Stereograms please follow this link:

Disturbing Presence
By Elias Schütt
( website, @elias94xx )
First JS1K entry! Not too happy with the result in FF and Opera, but at least it works.

Matrix is a system
By Pedro Franceschi
( website, @pedroh96 )
Matrix's digital rain animated in Javascript.

By Floriaen
( website, @floriaen )
Moving sunflower's seeds

Serious Stuff
By Pawel Waleczek
( website, @pwaleczek )
This does some serious eye-popping, brain-twisting, knee-bending stuff. Move the CURSOR or CLICK on it to get some. //updated and compresses with

Braille War
By Blaise Kal
( website )
A shooter for the visually impaired that takes place in your browser's address bar. Use arrows keys to play.

Color Factors
By Pablo Caro
( website, @pcaro90 )
Welcome to Color Factors! In this world, each point represents a number, starting from 2, to the infinite. Each one of these number is connected with its factors by an arc. The ... more

All the solutions of 8 queen puzzle
By Asen Bozhilov
( website, @abozhilov )
Finds all the solutions of 8 queen puzzle. It placing eight chess queens on an 8×8 chessboard so that no two queens attack each other. All the solutions are 92, it prints them.

Impressionist Flowering Trees
By Alejandro Mosquera
( website, @amsqr )
Simple L-system trees demo just to see how challenging size-optimizing JavaScript code is.

JSuper Mario 1k
By Vincent Thibault
( website, @robrowser )
Help Mario to rescue the (nonexistent) Princess Toadstool by running around this infinite world. Use arrows to run and jump, avoid falling into holes ! Sprite by @jseidelin. Opti... more

Flower of Life
By Tristan Brehaut
Randomly generated spiraling energetic patterns depicting the flower of life in 5 dimensions, or something :) Refresh window for a new flower.

Analog clock
By Max Bondar
( @Max_Bondar )
Simple analog clock

By Adam Dougherty
( website, @aJamDonut )
Color by pixel with colors, size and eraser.

By Nick Dandoulakis
( website, @ndandoulakis )
Bouncing balls demo.

By Francesco Trillini
( website, @Francext )
A spinner, with linear color cycle.

Spring Windmill
By Kevin Roast
( website, @kevinroast )
An colourful animation of a windmill in a field of spring flowers.

By Joachim Revol-Tissot
( website, @tsa_tse )
Displays a procedurally generated tree that grows and moves in the wind.

The 1k Notebook
By Claudio Cañete
( website, @claudiocc )
Skeuomorphic notebook page, including a 27 glyphs vector-based font, with handwriting animation algorithm. The complete font data is compressed in 259 bytes, with all the glyphs fr... more

By Zolmeister
( website, @Zolmeister )
An orderly storm

By Jérémy Tuloup
( @jtuloup )
Every year, spring is the time for renewal. It brings life back and buds grow again as the sun rise in the sky. If you want new trees, just refresh the page. Enjoy :)

hello #js1k
By Ioannis Cherouvim
( website, @cherouvim )
displays "hello" and "#js1k" with some funky moving letters

Infinite flowers
By David Mignot
( website, @idflood )
If spring would last forever...

By Ashley Bryant
( website, @ashesid )
Infinitely scrolls through a generated terrain. Click to generate a new one!

Texture Generator
By Ashley Bryant
( website, @ashesid )
Generates a random full coloured texture each time the page is refreshed.

By David Higgins
( website, @_higg )
Misuse of the HTML5 <progress> element.

Flower gun evader
By Mr Jason S
You must defeat the winter monster in order for spring to come. You are going to fight as Spring Warrior (blue circle) and he shoots flowers(representation of spring) to kill the... more

By Darren Schnare
( @darrenschnare )
Lineographic drawing app.

Slinky the Spring
By Eugene Mirotin
( @kennel_panic )
A slinky simulation

Vegas Slots
By Mike
Vegas Slots ------------------------------------------------------ Click to Spin and Win

Order out of Chaos
By Tristan Brehaut
Mouse interaction with an array of squares. Colored like spring time :) Mousedown to enhance the effect.

Slinky Pops
By Felix Woitzel
( @Flexi23 )
3 support particles (with mouse 4) and 3 springs + custom spline using a Bernstein polynomial of degree 6. Pop them bubbles! :D

Spring Bees!
By Mathieu Sylvain
( @masyl )
The spring bees come in spring, click and they will spring away!

Tank Duel
By Florian Maul
( @fmaul )
Scorched Earth clone for two players. Gameplay: - Adjust your browser window size for terrain sizes - Press F5 until you have a desired terrain and tank placement ... more

Daisy Chain
By Jon Faviell
( website )
Just some pretty unicode flowers that rotate and change colors. Updated to save a few more bytes. :)

Color Shift
By Jack Rugile
( website, @jackrugile )
This is a canvas demo that overlaps multiple circles drawn at a low opacity. The color shifts over time and the circles increase in size. The composite mode is set to lighter and t... more

Duckling Pond
By Ian Sullivan
( @iansullivan88 )
Control 'mother duck' with your mouse and watch her hatchlings follow.

Happy three ferns!
By Dmytro Mindra
( website, @dmytromindra )
Script draws three happy and animated Barnsley fern fractals.

By Felipe Alfonso
( website, @i_lovepixel )
Reveal the secret word!

By Sven Bergström
( website, @FuzzYspo0N )
3D projections in 2D, 50x50 grid mathed about with.

By ponce
( website, @p0unce )
Can't get enough shadowBlur.

Moiré's sun
By Antoine LE CALVEZ
( website )
It creates a circular moiré pattern, looks perfect on recent Firefox, not as good on Chrome

Dawn of butterflies
By Frank Cortes
( @franklyn_bdn )
What is a spring without butterflies? These butterflies are generated using Bezier Curves, and they are flying while the dawn starts.

By Evgeny Stepanishchev i LO
( website, @bolknote )
Use arrow keys to control your red tank (and SPACE to fire). You've to kill as many endless enemies as you can before you imminent die. You have 3 lifes and can get one for every 20 dead enemies.

Maze generator
By François CREVOLA
( @Krevo_ )
It randomly generates a maze ! Worth mentionning that the script is small enough to be in tweet !!