JS1k: The JavaScript code golfing competition

2017 - It's like magic

Home   Rules   Demos   Submit Mailing list  |  Update demo meta data  |  The /r/js1k subreddit JS1k, the yearly JS code golfing competition

Create some JavaScript program with a max size of 1k and make it do something cool. Submit it before March 2017 for fame and a chance of a prize! See rules for details and existing demos for some cool examples. Entry is free and the rules are simple. Give it a try, it"s really fun! Also see the intro by p01.


Together the hand picked jury will pick the top 10. They are a mix of JavaScripters and demo sceners.

Martin Kleppe

Martin went beyond the known limits of JavaScript many times. He is well known for his work like JSFuck, the spinning Globe in 1K, 雨, Invisible Code or Aurebesh.js. Now he talks at conferences around the world about "Creative Coding" – but still remembers, that JS1k is where he grew up.

@aemkei aem1k.com

Ruth John

Ruth is a web technologist and Google Developer Expert. She likes to educate people about new web technologies and inspire them to try them, coming up with exciting and engaging ways to use them. She’s a founding member of { Live: JS }, a collective of audio and visual artists that solely rely on JavaScript to create their performances. Her favourite things include interactive audio/visual installations and 80s cartoons, usually at the same time!

@rumyra rumyrashead.com

Ada Rose Edwards

Ada Rose Edwards is a Senior Engineer and Web Developer Advocate at Samsung Research UK. Currently focusing on Progressive Web Apps and bringing Virtual Reality to the Web.

@lady_ada_king ada.is

Ingvar Stepanyan

Obsessed D2D programmer (parsers, compilers, tools & specs), speaker and performance engineer. Currently speeding your code up at Cloudflare.

@rreverser rreverser.com


A competition has to have prizes. Below you see an overview of the prizes and who offered them.

50$ from you?

Ask — What's 50 bucks for any company, really? Ask your boss, ask yourself, ask a friend, donate some money and get everlasting fame on js1k.com


80 EUR

Peter van der Zee — Besides spending hours on end maintaining this website, he's also a JavaScript freelancer. Get in touch at c80.nl!


50 USD

Andrzej Mazur — HTML5 game developer from Enclave Games who organizes js13kGames compo and sends the Gamedev.js Weekly newsletter.



Below are the last 10 submissions. The rest is on the demos overview page. Or why don't you submit yours right now?

canvas Harmony

By Muhammad Rifqi Priyo Susanto
( @SRifqi )

Islamic geometric pattern with some song in the background.

pure mag1k

By Richard Sudaryono
( @gamehelp16, website )

A card magic trick in less than one kilobyte!

canvas "Screensaver"

By Alexey Temnykov

Move the racket (as soon as possible) and save your screen!

pure Can I haz 1Karrot?

( @MaximeEuziere, website )

The magician's rabbit has escaped the stage with its hat and is looking for his carrot in a strange forest... Move with arrows / WASD / ZQSD. Read the demo details if it looks bad!

webgl Night Flight

By Jonathan Brodsky
( @jonbro, website )

Heightmap raycaster with fm synth.

canvas Magical L-system

By Sergey Chernykh
( @sergonaut, website )

L-systems. See details. Copy this: {"step": 6, "orig": {"x": 0.1, "y": 0.1}, "dir": 20, "start": "F+", "angle": 90, "rules":["F=F+F-F-F+F"], "n":5}

webgl 1kloud

By Sos
( @Sosowski, website )

Pretty pretty cloud generation in 1k.

canvas 👧🏻ABRACADABRA!📚👺

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

Abracadabra - Spook at the wizard library

canvas Recursive Trees

By Scott McGann
( @c4ntelope, website )

Recursive Fractal Trees

canvas Boulder Dash

By Ates Goral
( @atesgoral, website )

Use arrow keys to reach the exit on the bottom right.