JS1k: The JavaScript code golfing competition

2017 - It's like magic

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Check out demos from previous editions too! 2010 , 2010 , 2011 , 2012 , 2013 , 2014 , 2015 , 2016 , 2018 , 2019


By Eric
( @ericrosbh )

Evolution of species in 1k

Star Gate

By Miloš Popović
( @mochapoetaster )

Join Dave on his magical trip trough the Star Gate


By Evan Hahn
( @EvanHahn, website )

Click to see new potions.


By therealjampers

retro 3d fun, uncross your eyes to see the magic pattern - respect to all the js1k mag1k sceners :-)

sin city

By Shuichi Aizawa
( @switchstyle, website )

click to switch between 4 modes

retro neon (where is the magic)

By alternative451

Simple retro neon effect / mouse pos sensitive

Watercolor artist

By Siorki
( @Siorki )

The artist is busy painting a lavender field, but give him any other model (upload an image file) and he'll immediately start working on it.


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

Audio Visual LIVE coding environment for the Twitter generation.

Magic Powder

By Michiel de Jong and Wiebe-Marten Wijnja
( @wiebemarten, website )

Use your mouse to place elements (and the scrollwheel to change the selected element).


By Michał Skowronek
( @coderitual )

Stolen from AI.

Magic circle drawing

By Piotr Stosur

Simple graphic program to draw mandala-like shapes.

Neon Pond

By Zolmeister
( @Zolmeister, website )

Ripple Reality


By Anders Thøgersen
( @aklt00, website )

Navigate the maze and gather mana avoiding the green slime and merrily discharge digestive juices.

SVG Tangram

By Chris Richards
( website )

Mobile and Desktop Tangram using SVG and filters.


By Graham Licence
( @grahamlicence, website )

Watch or click to relocate


By Lexx918
( @Lexx918, website )

Cubes are flying in the face. Unbelievable!


By Alexey Temnykov

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


By jacklehamster
( @jacklehamster, website )

Looks pretty... don't ask me what it does. I just wrote random code, and this is the result.

Peter De Jong attractor

By Dyno
( website )

Visualize the attractors of a dynamical system. Click to randomize parameters.

The Internet Tunnel

By Lucien Boudy
( @hatscat )

Visually inspired by funny images you can see by searching "internet tunnel" on google images (https://www.google.fr/search?q=internet+tunnel&source=lnms&tbm=isch).

Magic Draw

By Stephen Cunliffe
( @scunliffe, website )

Click and drag to draw with magic!

"Safari" Opera

( website )

Somewhere in the universe, at the setting of one of its suns. Birds fly in the sky to the sound of insects, while the wind caresses the herbs ...

Diva's Magic Dream

By Oscar Toledo G.
( @nanochess, website )

The diva is dreaming, stop fans & destroy moai heads! left/right arrows, space-shoot magic. Now with happy sun and cameras! ;)


By Fabio Vergani

Color mix like oil/water


By Aurélio Santos
( @therealaurhe )

Use arrow keys to drive the car.

animal magic

By martin
( @lolcontrol )

a vortex of cute emojis

osmos 1k clone

By brzez
( website )

Game similar to the Osmos game (by Hemisphere Games) which i kinda liked.

Flow of Illusions

By Jani Ylikangas
( @jylikangas, website )

Shows 3 different ways to animate that magical logo.


By Ioannis Cherouvim
( @cherouvim, website )

Bitcoin = Magic Internet Money

Friendly cube raymarcher

By Jonas Höglund
( @FireyFly, website )

(GPU-intensive) WebGL (GLSL) raymarcher. Use <Left>/<Right> to rotate the cube and re-render it.

Leap of Faith

By Rebecca
( @veubeke, website )

Controls: left and right arrow keys to move, up to levitate.

The Godess Thriai

By rauri
( @raurir, website )

The ancient insects dreamed of a goddess; Thriai, who created her photonic hives in the stars and from there her sisters transmit their instructions to the drones below; signal by signal, scent by sce…

The Arecibo Message

By Tommy Hodgins
( @innovati, website )

Watch and listen to the Arecibo Message like an alien civilization intercepting an interstellar transmission from earth!


By Josep del Rio
( @joseprio, website )

Use your mouse to rotate the stars and reveal the hidden images

Linked Dots

By Infernet89
( @infernet89, website )

Move dots until connection do not intersect. Each level will have 1 more dot, and become easier overtime.

PERIOD1k reloaded

By The Codegolf Team
( website )

The periodic table of chemical elements, including type, name, atomic number, atomic mass, stability and state at room temperature for each of the 118 elements!

Maze Generator

By Bernard Perrin

Maze Generator inspired by D. Shiffman's Coding Challenge

The Mathemagician

By James Wright
( @jamesseanwright, website )

The Mathemagician loves solving difficult multiplications on the spot. One could almost argue that it's magic...

1Kind of magic

( @MaximeEuziere, website )

Couldn't let go this year's theme without a 1kb interpretation of Queen's "A kind of Magic"!

Boulder Dash

By Ates Goral
( @atesgoral, website )

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

Divining Dust

By walsh9
( @umrain, website )

Glimpse into subconscious thoughts and possible futures


By Shotgan & frikeldon
( website )

Raymarching shader in 1K. No interactive this time.

Magic Hat

By Nick Matantsev
( @unframework, website )

Control the magic hat with your mouse

Point Contain

By Xanmia
( @Xanmia, website )

Your mouse repels the 5000 points of the circle, try containing these points within your screen using your mouse. Lose one and time is up.


By Chris Hallberg
( @crhallberg, website )

Arrow keys to move a number of spaces equal to the adjacent number in that direction. You can't cross your path. Try to clear the board.


By Muhammad Rifqi Priyo Susanto
( @SRifqi )

Islamic geometric pattern with some song in the background.

Magic Flute

By Lara
( @literallylara )

With sincere apologies to Wolfgang Amadeus Mozart

Little Pegasus

By shining_armor

Collect white clouds


By Richard Sudaryono
( @gamehelp16, website )

A card magic trick in less than one kilobyte!

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!

Night Flight

By Jonathan Brodsky
( @jonbro, website )

Heightmap raycaster with fm synth.

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}

Classic magicians trick

By Ashley
( @ashesid, website )

Some magic in the magicians hat!


By Sos
( @Sosowski, website )

Pretty pretty cloud generation in 1k.


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

Abracadabra - Spook at the wizard library

Recursive Trees

By Scott McGann
( @c4ntelope, website )

Recursive Fractal Trees

Magic Circle

By Mark Vasilkov
( @mvasilkov, website )

So magical it has right angles!

Circles of Magic

By fractalf

Playing with fractal cirlces, inspired by "circle magic !gi"

Pythagoras tree

By Nedim Dedic
( @nedimdedic075 )

Interactive Pythagoras tree fractal

RG Worm

By Andrew Berry
( @andybberry )

Controls: up and down to move. Potions: red = faster, green = slower.

If the moon was 1px...

By The Codegolf Team
( website )

The moon measures 1px. All the solar system (Sun, 13 planets, 21 moons and 161 minor satellites) is drawn to scale in a very long HTML page and with an extreme precision.


By jullien
( @https://github.com/julien )

A little bubble walking on the screen


By Per-Olov Jernberg
( @possan, website )

A small sudoku game with variable difficulty


By RasmusErik Voel Jensen
( website )

chaotic attractors

By thom (tcsc)

click to generate a random chaotic attractor

Gesture Detector

By Huỳnh Trần Khanh
( @CrazyKranzy )

Draw something, give it a name, draw it again and see.


By Josep del Rio
( @joseprio, website )

Turn over the cards and match the animals


By xen
( @xen_the )

-[=[Dare To Stare]=]-

Code Compression

By RasmusErik Voel Jensen
( @kodekunstner, website )

Compress source code to self-extracting JS

Catch the Snitch

By Richard van der Dys
( website )

Visualization of a seeker trying to catch the snitch.

On Golden Pond

By Josh Friedson
( website )

Just sit back and watch the pretty sparkles fill up the screen with a pond of magic-like goldenessess. *Disclaimer: Not the actual pond used in the movie.*

Line Engine 1K

By zb3
( website )

Nothing sophisticated, just moving lines... Use mouse drag / tap to change the scale origin.

Solar System Game

By Viktor Kovacs
( website )

One click to place new planet, another click to define speed and direction. Try to create as many orbiting planets as you can.


By Larix Kortbeek
( @larixk, website )

Emergent visual effect coming from stacked canvas rotation and scaling.

Red Magic

By Felipe Alfonso
( @bitnenfer, website )

I originally wanted to make a cellular automaton implementation. But I thought the effect looked nice and like fire, so I played with it.


By Gaëtan Burg
( @tag9724 )

Click quickly on the black boxes before the time end !

Mouse/Touch Toy

By Scott McGann
( @c4ntelope, website )

Interactive mouse/touch toy.

Eat Magic Pills

By Stephen Cunliffe
( @scunliffe, website )

Use arrow keys, eat magic green pills, grow big, avoid the enemy

3D Engine

By Scott McGann
( @c4ntelope, website )

A 3D graphics engine in 1011 bytes.


By Michael Vogt
( @neophob, website )

NO SIGNAL shows an EBS TV screen featuring visual glitches.


By Fabio Manna

A relaxing Snake game


By Rafael Vilela

Gotta break all the blocks! Use left and right arrows to move and spacebar to shoot.

1k Quadtree

By James Milner
( @JamesLMilner, website )

A quadtree highlighting mouse position, using DOM nodes and JavaScript


By Gabor Bata
( @gabor_bata, website )

Clear the field by removing groups of more than one colored square; the larger the group you remove, the more points you get.

Catch the wizard!

By michele diegoli
( @morticcino )

I love make "teletext style" games! Here a simple game! Hope you enjoy!

pure js ray tracer

By Igor Sbitnev
( @ISbitnev )

Pure javascript raytracer, without WebGL, completely software rendering.

Mini Shadertoy

By The Codegolf Team

Create WebGL shaders, share them via URLs, and see the result live! Inputs: iResolution, iGlobalTime, iTimeDelta, iFrame, iMouse, iDate. Double-click for fullscreen.

3D Cheese

By Scott McGann
( @c4ntelope, website )

Yet another particle system.

Interactive Drawing

By Scott McGann
( @c4ntelope, website )

Colorful mouse toy.


By Tyler

Fireworks, clocking in at 968 characters.

Twisty Particle Field

By Scott McGann
( @c4ntelope, website )

Demo uses a minified version of my 3D engine: http://cantelope.org/3D


By Bobrov Vladimir

Select two line indicators to swap them. Select line indicator twice to overturn it. You need to make every quarter filled by one color!