JS1k: The JavaScript code golfing competition

2015 - The JS1k hype train is real!

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Check out demos from previous editions too! 2010 , 2010 , 2011 , 2012 , 2013 , 2014 , 2016 , 2017 , 2018 , 2019


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

IMPOSSIBLE ROAD is a pure, minimal arcade game about risk, reward, and rollercoasters.

Warp Drive Train

By Greg Tatum
( @TatumCreative, website )

Hop onto the hype train to the next galaxy!


By Siorki
( @Siorki )

A space probe warp jumps from star system to star system, in a quest for a planet that could harbor life.

Cubic Train

By Josep del Rio
( @joseprio, website )

Raytraced voxel train. That's it!

Minimal Miner

By Michiel de Jong
( website )

Use WASD to move, shift to mine. Mine the gold and avoid the monster bats.

Connect Four 3D

By Oliver Güther
( @MagnitudoOrg, website )

Click on the field to position your ball! Click BELOW the field to confirm your move and let the AI work. The winner will be hyped.


By Cris Stringfellow
( @1arity )

Make your own DEMO with a JavaScript REPL in 1K of JS (includes self-extracting LZW). Supports console log and error and Ctrl Enter makes a new line, and Enter executes. If you want to live mod anothe…

Melting snow

By Piotr Stosur

Winter is almost gone and the snow is starting to melt away.

Physics Hype 3D

By Fredrik Karlsson
( @kaibaLAB, website )

Physics Hype - 3D physics engine - click or reload to drop another spinning object - full screen for best effect.


By RhinoBear Industries inc.
( website )

Creates an awesome fractal wherever you click. Refresh to get a new fractal!

Audience is Listening

By Uri

The Audience Is Listening.

Do the Wave!

By Alex Patton

2d wave simulation. Click and drag to make waves, WASD to rotate, P to pause.

Rainbow Noise

By Tom Hargreaves
( @hexwab, website )

Noise generator, in all colours of the rainbow.

1k FM Synthesizer

By Joseph Culbert
( @neckro, website )

Play notes with bottom row of keyboard. Try "f" in freq field.

Train Ride

By Andre Nanninga

An isometric view of a peaceful train trip through a never-ending forest.


By Philippe Deschaseaux
( @ehouais, website )

Procedural generation of islands (arrow keys/PgUp/PgDown to explore)

The Trolley Problem

By Thibaud Colas
( @ThibWeb, website )

Will you kill those people, or try to spare them?

Mysterious Monorail

By homecoded / DESiRE
( @homecoded, website )

Ride the mysterious monorail through a misty metropolis (1:50 mins)


By Dan Efran
( @Dan_Efran, website )

Click to switch which train is faster. Don't let them collide! Smaller window = bigger challenge.


By Bence Szabo
( @benny_szabo, website )

SVG Analog Alarm Clock with Sound. Click or tap (works on mobile too) on the clock face to set or reset the alarm (red hand)

Find a color

By Sergey Chernykh
( @sergonaut, website )

Find (click) a rectangle that has the same color as the circle. The clock is ticking!


By Maxime Euziere
( @maximeeuziere, website )

The first 4D demo on JS1k! Move your mouse to start the demo and move the camera. Use the buttons to customize and animate.

Infinite Star Field

By Eduardo Lopes
( @EdoardoLopes, website )

A random infinite star field! You can drag the map using the mouse! Should work on touch screens as well!

Particle Party

By HellMood / DESiRE
( website )

One million particles, raving to the beat ♪♫ Soundsystem & Fullscreen recommended!

Train Window

By Reinder Nijhoff
( @reindernijhoff, website )

View of passing landscape from a train window. Winter is coming: wait for lakes, the night and more.

Build Track Quickly

By Stephen Sherratt
( website )

Make a circuit by placing corners before the train runs out of track. Click to place tiles, press any key to rotate 90 degrees.


By Keith Clark
( @keithclarkcouk, website )

Inspired by the classic arcade shooter Defender. Use the arrow keys to fly and space to fire.

The Love Train

By Pat Cullen
( @patcullen, website )

What train do you choose to travel through life on?

70's Screensaver

By Ville Hellman
( @efexen, website )

Couldn't come up with anything on topic but thought this was pretty neat and might inspire someone.

Pulsating colour wheel

By Ashley
( @ashesid, website )

Sit back and enjoy the ride.

1k Rail Sim

By Nik Coughlin
( website )

Build strategically to earn $10k before time is up, click: water to terraform, land to place station. Clear 5 levels to win.


By Felix Woitzel
( @Flexi23, website )

This is a homage to last year's entry DragonDrop - a recursive depth limited variant of the Dragon curve


By misantronic
( @misantronic, website )

A Space Invader clone. Invaders from outer space are coming to kill your mom! (http://codepen.io/misantronic/pen/yyLGVa, 502 bytes)

Murder Train

By Petter
( website )

A whodunnit set on a train.

Amass v.2

By Xen

My first attempt at js1k.

Train Hyper-Tunnel

By Jarrod Connolly
( @JarrodConnolly, website )

Super fun hyper-tunnel for your train!

Track Cre-A-Tor

By Xanmia
( @Xanmia, website )

Click to change piece and press any key to place selected track.

Tear the curtain!

By Eugene Formanenko
( @mo4islona )

Control: M-switch mode G-toggle gravity V-show all vertices

Ascii Blobs

By Analog
( @analogp1xel, website )

Ascii blobs within a html textarea

Train maze

By Sir Anthony
( @_SirAnthony )

Connect cities with tracks: click to build rails, click again to change direction.

Galaxy1K v1.1

By Nikola Fox
( @juusu )

A WebGL galaxy made out of 70000 particles!


By misfits

UP: up, DOWN: down. Avoid obstacles and epilepsy :)

Canvas Feedback 1K

By Chris Pressey
( @catseye_tc, website )

For the patient: watch it unfold. For the impatient: click and drag.

Evolution of Hype

By Rebecca and Rauri
( website )

An interactive simulation of hype.

Cosmic railways

By subzey
( @subzey )

Retrofuturistic intro

Trains are canvases

By Triskaideka
( website )

Enter some text (lowercase letters and spaces only) and it'll be drawn in graffiti-style lettering.


By Muhammad Rifqi Priyo Susanto

Dakon (Javanese Congkak)

miniMAL Lisp

By Joel Martin
( @bus_kanaka, website )

A Clojure inspired Lisp-0 with automatic tail-call optimization (TCO), JavaScript interop, first class functions, lexical scope, let blocks, function closures, variadic functions, and JSON syntax.

mini shoot'er

By Luis Toledo
( @digitalcth, website )

WASD to move, MOUSE to aim and shoot


By Jack Rugile
( @jackrugile, website )

Move mouse to focus energy and click to regenerate.

Rave hype train

By Michal Paszkiewicz
( website )

Some hyped rave in that train over there!


By Mark Vasilkov
( @mvasilkov, website )

Monumental (Hall of Pillars)

Perlin mesh

By Andrea Venuta
( @veeeeenu, website )

A 500-ish bytes implementation of Perlin's noise primitive plotted with WebGL.

Wheels of the train

By Peter van der Zee
( @kuvos, website )

go round and round. And round. And round. Move mouse for psychedelic effects.


By Bubori Attila
( @buboriattila )

JumpTrain: Click or Tap to JUMP.

Rail network

By Hussein Taher

Click somewhere to add new train stations. Earn more money by travelling passagers and build more stations.

The Hub

By Jeremy Tuloup
( @jtpio, website )

The Hub is a place where trains meet and cross each other, day and night, non-stop.

Not a fractal

By Infernet89
( @infernet89, website )

Trust me, i am not a fractal!


By Evan Hahn
( @EvanHahn, website )

Tell time with pie charts.


By therealjampers
( @therealjampers )

Enigma machine simulator (Wehrmacht M3) with a choice of 3 out of 5 rotors (I, II, III , IV, V) a choice of 1 reflector from 2 (B, C wide) and configurable plugboard settings. Type alphabetical keys!

Train Ride

By Philip Wagner
( @houly, website )

A train ride through day and night.


By Elias Schütt
( @elias_schuett, website )

I like trains

By Maxime Euziere
( @maximeeuziere, website )

A tribute to asdfmovie. I like trains.


By Per-Olov Jernberg
( @possan )

WebGL Starfield, wobbly camera and rails!


By Sampo Savilampi
( website )

Should work in all major new browsers.

Moscow Metro at Night

By Nokeya
( @ololopepyaka, website )

Moscow Metro at midnight.

Trans Nevada Express

By Daniel Bali
( @balidani )

Just a train passing through a desert. Now with 100% more shooting stars.


By Eugene Lapin
( website )

Most popular solitaire card game.

Mini Games Collection #2

By The Codegolf team

Two mini JS games: Simon and 2048!

Pixel Space Train

By Harry Scells
( @hscells, website )

Ride on the top of the hype train through space.

Amass v1

By Xen

My first attempt at js1k,


By Richard van der Dys
( website )

Simple Tower Defense Game


By Martin Kleppe
( @aemkei, website )

The raining code sequence that prints its own source code using only Asian characters.

Choo choo

By Martijn de Boer
( @sexybiggetje, website )

Renders a working ascii train with a sinescroller on it, because every demo needs one.

Take me to the train!

By Infernet89
( website )

Use arrows to take the correct passenger to the train!


By Zolmeister
( @Zolmeister, website )

Zop - A Game - Zolmeitser

Crystallization Hype

By Erik Engi
( @kireerike, website )

Examine the crystallization hype! Draw some new colorful crystals with your mouse! Click or hold down it to feel the magic! Hope you are having fun and enjoying the hype!

no man's hype

By dividead
( @Ux3F3A )

most hyped game of 2015

Polyphonic Piano

By Roland Bouman
( @rolandbouman, website )

A polyphonic piano based on web audio API. Use your computer keyboard to play the piano. Also, plays a 4-part rendition of the popular canon Frere Jacques. Works in Chrome, Firefox, Opera, Vivaldi, bu…

Mini Apps Collection

By The Codegolf team

7 apps in 1kb! Mini Code Editor, HTML & CSS minifier, hex viewer, dataURI converter, spritesheet and JSPerf!

Platonic solids

By Viktor Kovács
( @kowik1984, website )

Platonic solid viewer. Click to change shape.

ASCII Art Battle

By Richard Sudaryono
( @gamehelp16, website )

A simple game where you fight against a dummy bot, get coins, upgrade your sword and armor, fight harder dummy bot, and so on.

JS1k 2015 Invitation

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

JS1k demo invitation for JS1k 2015.


By christoffee
( @christoffie, website )

Press ANY key to derail the train. Avoid the RED squares and collect the GREEN squares. REFRESH page to restart game.

Strange Crystals III

By Philippe Deschaseaux
( @ehouais, website )

Strange Crystals III, now theme-related: an appetizer for this year's contest

Mini Games Collection #1

By Codegolf Team

A collection of three mini JS games: Mine Sweeper, Pop Tiles, and Game of Life!