JS1k: The JavaScript code golfing competition

2013 - Spring!

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Check out demos from previous editions too! 2010 , 2010 , 2011 , 2012 , 2014 , 2015 , 2016 , 2017 , 2018 , 2019

Flower Warfare

By Teddy Cross
( @tkazec, website )

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 local storage and pre…

Plasma Flowers

By Josep del Rio
( @joseprio, website )

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
( @aklt00, website )

You are a moth flying through the night eating the tasty nectar from the flowers and avoiding bumping into things.

Strange crystals II

By Philippe Deschaseaux
( @ehouais, website )

The crystals have disappeared in the space/time fracture, but shiny Furbee has survived and is now accompanying the visitors.

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.

A Garden in Spring

By Steve Taylor
( @gostay, website )

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.

In Bloom

By Tim Smith

New life bursts forth, heralding spring's arrival!

Over The Hills

By Joshua Koo
( @blurspline, website )

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.

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.

Flower Power

By Manel Villar
( @galchwyn, website )

When Spring starts, flowers of all colours appear in the field

Catalan Nyan

By Raimon Ràfols
( @rrafols, website )

A Catalan flag waving + a star doing the nyan.cat ;)

Anaglyph Pong

By Aurélio A. Heckert
( @aurium, website )

Put your red+cyan glasses and play pong as you should do inside 1k TRON world.

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.

very strange attractors

By chris mckenzie
( @emorobot, website )

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.

Fractal Typography

By Adis Hamzić
( @hamzadis, website )

The Spring unwinds and Summer comes forth, rejoice! But better get a cup of coffee first, this might take a while...

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
( @wridgers, website )

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.

Underground Chamber

By Timothy Volp

A dark, cold, underground chamber deep below the surface of the earth.

Text growth

By grgrdvrt
( @grgrdvrt, website )

Type, press enter and let Mother Nature do the job

Daisy Chain

By Yann 'Aaunel' Eves-Hollis
( @aaunel, website )

Generates a random chain of blooming daisies!


By Tom Hargreaves
( website )

Plays a tune

3013 The 䕵 space-time fracture

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

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.



Picross/Nonogram/Hanjie Puzzle in 1K of JS.


By Yang Bin Kwok

It doesn't need to warm up! Written while waiting for mine to warm up...


By Evan Hahn
( @EvanHahn, website )

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 strokes it took. Do…

Julia Fractal Browser

By Doug Haber
( @LeshyLabs, website )

A Julia Fractal Browser with Stripe Average Coloring.

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:


By Benjamin Bill Planche
( @b_aldream, website )

Pointillist representation of an animated landscape: watch Spring comes and passes, and moving shadows casted by clouds.

1024 byte sequencer

By Per-Olov Jernberg
( @possan, website )

Expression based webaudio sequencer and sampler

Spring source

By Małgorzata Jatczyk
( @dcwebdev20, website )

Simple colourful bokehs.

1K Meteors

By Oscar Toledo G.
( @nanochess, website )

Pilot your ship through space and remove meteors from field. Rotate with left and right arrows, advance with up arrow, shoot with spacebar.

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
( @willscott, website )

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 Frazer's blog report o…

Springy Blobs

By Grant Kot
( @kotsoft, website )

Attract nearby blobs by moving the mouse. Simulates several hundred blobs, collisions between them, and collisions with a sinusoidal terrain.

1Keyboard 100Friends

By Pyrofoux
( @Pyrofoux, website )

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 springtheme name of the game is "ZombieS…


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
( @currankelleher, website )

Circles bouncing around and colliding. Click and drag to attract them to your mouse. Learn how it was coded at http://www.youtube.com/watch?v=yF0T7lviBnY

Game of Life

By Daniel Bali
( @balidani )

Simple Conway's Game of Life implementation


By Derek Ries
( @derek_ries, website )

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
( @haengebruegge, website )

Your are the spring Sun, the yellow square on the bottom.

Super Mini Hexagon

By feiss
( @feiss, website )

Fully playable Super Hexagon clone (http://superhexagon.com/)


By James Allardice
( @james_allardice, website )

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
( @dotfury, website )

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.

A live anime-like picture: have you ever tried to catch a firefly?

By Carlos Reventlov
( @xiam, website )

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 Opera and all of that w…

Furbee, get out of that tunnel ASAP!

By Roman Cortes
( @romancortes, website )

This is a tribute to amazing Strange Crystals by @ehouais (http://js1k.com/2013-spring/demo/1459). As my original Furbee entry (http://js1k.com/2013-spring/demo/1451) and ehouais' entry went viral/Sla…

Winter Wrap Up

By Rebecca
( @veubeke, website )

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.

Strange crystals

By Philippe Deschaseaux
( @ehouais, website )

"The miners have stopped working. They are afraid. It all seems to come from those strange crystals that some have seen."


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.

April showers bring May flowers

By Abigail Cabunoc
( @abbycabs, website )

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 - you only have five…

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 show you around.

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
( @romancortes, website )

Spring bee with springy antennae and my trademark tie from my logo/website.


By Siorki
( @Siorki, website )

Helicopter simulation, tribute to the game Comanche : Maximum Overkill.


By Arct1k

It says it with flowers

Don't worry, bee happy!

By Manuel Rülke
( @homecoded, website )

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 morning."


By Benjamin Bill Planche
( @b_aldream, website )

"They said I could be anything..." - 3D Mesh

Mars Rover

By Ashley Bryant
( @ashesid, website )

Take a tour over a randomly generated 3D map.


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;

Matrix style Conway's Game of Life

By Asafh
( @asafhd, website )

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
( @KaeruCT, website )

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 frame, no other kind…

Water Spring

By Asad Memon
( website )


☺ Puzzle

By Mikhail Davydov
( @azproduction, website )

←↓→ & try to collect all ☺!


By Alex Turpin
( @AlexandreTurpin, website )

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 objects. Also, the colli…

Math Graphs

By Mohsen Azimi
( @mohsen____, website )

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
( @pulsar64, website )

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.

One more kilobyte

By Inopia

Flat shaded metaballs using marching tetrahedrons. Use Chrome for best results.

tiny solar system

By Marco Pro Campos
( @marcospc69, website )

tiny solar system

Treasure Quest

By Philip Wagner
( @houly, website )

An exciting dungeon crawler. Features:

Stick JS

By Damian Cipolat
( @DamCipolat, website )

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.

Simple Sequencer

By Rebecca
( @veubeke, website )

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 garble your code to mak…


By Elias Schütt
( @elias94xx, website )

My third and final submission. :)

Animated 3D SIRD Plasma

By Philipp Stucki
( @_phst, website )

Animated 3D plasma rendered using a single image random dot stereogram (SIRD). Read http://en.wikipedia.org/wiki/Autostereogram#Viewing_techniques on how to view a SIRD.

Tunnel Racer

By Pim Linders
( @pimlinders, website )

Find your way through the winding tunnel -- but don't hit the wall!

Simple Piano Recorder

By JiminP

Press keys(ZSXDCVG.. and Q2W3ER5...) to play the piano.

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.

swirled tree

By lacemaker
( website )

just another randomly generated pythagoras tree

Falling Letters

By Imran Latif
( @ilatif_bwp, website )

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?


By bga_
( @bga_ )

bit hard xonix, fitted into 1k

Drop The Ball

By Steven Scott
( website )

Drop the ball game. Use the left & right cursor keys to keep up with the ledges.


By Tamas Kalman
( @dh2k, website )

A classic demo scene plasma effect using floating point operations.

The Game Of Go

By Ben
( @shobute, website )

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 descending towards…


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.

Living Code

By Elias Schütt
( @elias94xx, website )

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: http://en.wikipedia.org/wiki/Autostereogram

Disturbing Presence

By Elias Schütt
( @elias94xx, website )

First JS1K entry!

Matrix is a system

By Pedro Franceschi
( @pedroh96, website )

Matrix's digital rain animated in Javascript.


By Floriaen
( @floriaen, website )

Moving sunflower's seeds

Serious Stuff

By Pawel Waleczek
( @pwaleczek, website )

This does some serious eye-popping, brain-twisting, knee-bending stuff. Move the CURSOR or CLICK on it to get some.

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
( @pcaro90, website )

Welcome to Color Factors!

All the solutions of 8 queen puzzle

By Asen Bozhilov
( @abozhilov, website )

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
( @amsqr, website )

Simple L-system trees demo just to see how challenging size-optimizing JavaScript code is.

JSuper Mario 1k

By Vincent Thibault
( @robrowser, website )

Help Mario to rescue the (nonexistent) Princess Toadstool by running around this infinite world. Use arrows to run and jump, avoid falling into holes !

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
( @aJamDonut, website )

Color by pixel with colors, size and eraser.


By Nick Dandoulakis
( @ndandoulakis, website )

Bouncing balls demo.


By Francesco Trillini
( @Francext, website )

A spinner, with linear color cycle.

Spring Windmill

By Kevin Roast
( @kevinroast, website )

An colourful animation of a windmill in a field of spring flowers.


By Joachim Revol-Tissot
( @tsa_tse, website )

Displays a procedurally generated tree that grows and moves in the wind.

The 1k Notebook

By Claudio Cañete
( @claudiocc, website )

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 from a to z and an add…


By Zolmeister
( @Zolmeister, website )

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.

hello #js1k

By Ioannis Cherouvim
( @cherouvim, website )

displays "hello" and "#js1k" with some funky moving letters

Infinite flowers

By David Mignot
( @idflood, website )

If spring would last forever...


By Ashley Bryant
( @ashesid, website )

Infinitely scrolls through a generated terrain. Click to generate a new one!

Texture Generator

By Ashley Bryant
( @ashesid, website )

Generates a random full coloured texture each time the page is refreshed.


By David Higgins
( @_higg, website )

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.


By Darren Schnare
( @darrenschnare )

Lineographic drawing app.

Slinky the Spring

By Eugene Mirotin
( @kennel_panic )

A slinky simulation

Vegas Slots

By Mike

Vegas Slots

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.

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.

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
( @jackrugile, website )

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 the canvas is cleared…

Duckling Pond

By Ian Sullivan
( @iansullivan88 )

Control 'mother duck' with your mouse and watch her hatchlings follow.

Happy three ferns!

By Dmytro Mindra
( @dmytromindra, website )

Script draws three happy and animated Barnsley fern fractals.


By Felipe Alfonso
( @i_lovepixel, website )

Reveal the secret word!


By Sven Bergström
( @FuzzYspo0N, website )

3D projections in 2D, 50x50 grid mathed about with.


By ponce
( @p0unce, website )

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
( @bolknote, website )

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 !!