JS1k: The JavaScript code golfing competition

2016 - Let's get eleMental!

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Check out demos from previous editions too! 2010 , 2010 , 2011 , 2012 , 2013 , 2014 , 2015 , 2017 , 2018 , 2019


By Michał Skowronek
( @coderitual )

Simple one mouse button game. Run from the blue enemies.

Real Molecules

By Oliver Güther
( @MagnitudoOrg, website )

Explore 30 real molecules like alcohol, acid, ether, methane, ethane, ammonia, amines, water... Wait 3 s or refresh to speed up, see descr.

Binary Music Machine

By Lutz Rosema
( @terabaud, website )

Simple binary counter, where every bit represents a tone. Generates an interesting melody :)

Elemental master

By Oscar Toledo G.
( @nanochess, website )

Catch the yellow atoms, don't touch red ones. Move left and right touching your screen or using keyboard.

3 Card Klondike

By Eugene Lapin

Most popular solitaire card game

Rubik's Cube

By Nadeesh Peiris
( @Nash171 )

rubik's cube animation using CSS3 and JS


By Graham Licence
( @grahamlicence, website )

Mouseover or click to populate

JS Hacker Typer 1K!! Yeaaah!

By Guillermo Espada
( @_gui64 )

Really simple hacker typer. Outputs randomly generated JS code.

Gliese 581 c

By Philippe Deschaseaux
( @ehouais, website )

Ground level flyby of an inhospitable planet (arrows to turn left/right)

Fractal eleMental

By fractalf
( website )

Dive into the evolving structure of mental elements


By Uri

The start screen of a fictional game called Elemental.


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

And the beat goes on in the LORENZ SINGULARITY!

ZX SCREEN$ Capture

By therealjampers

Capture a ZX Spectrum compatible SCREEN$ ".scr" file for your latest demo, or simply watch realtime glorious speccy-vision from your webcam

Coral Reef

By HellMood / DESiRE & Lara
( @literallylara )

Sit back and enjoy a tour through the mystic seas (chrome for best ♪♫)


By Ioannis Cherouvim
( @cherouvim, website )

The search for utopia always fails. So, spend your energy on something else.


By Evan Hahn
( @EvanHahn, website )

Click for colorful fireworks!

Match Atomic Number

By Muhammad Rifqi Priyo Susanto
( @SRifqi )

This game will test you about the Periodic Table - UP or DOWN key or tap top or bottom canvas to play.

Krasnodon's Salute

By Alexey Temnykov

If you will be ever late for the celebration, don't worry, enjoy!

Water Gate

( website )

Up the volume, move your mouse to drop your finger in the water and see the tail ! Better experience in 1920*1080 ..


By Khoi Nguyen
( @potasmic, website )

Particles, wall collision, wacky peer-collisions, particle-pursuit. Click anywhere to spawn a swarm :)


By Michael Vogt
( @neophob, website )

LAZER, 1984 edition. Oh look, planets and mountains are moving...

Art in '92

By Siorki
( @Siorki )

She started dancing almost a quarter century ago ! Tribute to a demo that redefined the Amiga scene back then.


By Quinten Clause
( @quintenclause, website )

wandering things

The Secret of Mental Island

By Manuel Rülke / homecoded / DESiRE
( @homecoded, website )

A tiny player that can play songs composed in Renoise tracker, wrapped in a tribute to Monkey Island.


By daniele pascal morelli
( website )

Left:volume, Right:variance, ?:random. Be the alien dj! Needs web audio api support. Have fun!

Romanesco 2.0

By Lara & HellMood
( @literallylara )

Move your mouse to change the shape and listen to mystical sounds.

They don't know where to go

By LuisQuin
( @LuisQuin9000, website )

Basing their movements and reactions on a tiny Perlin noise implementation, those hundred small living things don't know were to go.


By Chris Hallberg
( @crhallberg, website )

Monochrome is puzzle game where the goal is to make all the tiles the same color. Press any key to restart a level.


By Krisztian Toth
( @krisszhu, website )

Upload an image and watch it on an old CRT TV!

Attack of the Mutant Elements

By Manel Vilar
( @galchwyn, website )

The Elements are attacking the Earth. Press space to defend it from them. Go!

Under a yellow sun

By Ashley
( @ashesid, website )

Growth of some randomly generated plants.

Dark Star

By LuisQuin
( @LuisQuin9000, website )

Based on a tiny Perlin noise implementation, this very inestable Dark Star is probably going to explode in a few billion years.


By Jason Plackey

How it all started...

element of fun

By martin
( @lolcontrol )

a nice emoji that expresses joy

Low poly animals

By Damian Cipolat
( @damcipolat, website )

It is a simple example of how to draw animals using only triangles . The figure of moose was extracted from the site http://species-in-pieces.com/


By Rebecca
( @veubeke, website )

Controls: arrows and space. Someone’s setting off fireworks in the forest. What happens next will…

Elemental Entropy

By James Wright
( @jamesseanwright, website )

Protect the combustible oxygen from heat and fuel! Move the mouse left and right to rotate the shield around the oxygen particle.

Strange Attraction

By Thomas Bladh
( website )

Visualization of a Lorenz attractor for ρ = 28, σ = 10, and β = 8/3.

The Big Bang model

By Nino Camdzic
( website )

The Big Bang model

Dancing Planets

By Igor Zinovyev

Watch slow orbital evolution of gas giant planets.


By platane
( @platane_, website )

three swarms compete to collect minerals

Gnomes and Salamanders

By Michal Paszkiewicz
( website )

Use your arrow keys to avoid the salamanders hitting your gnome!

Elemental Knot

By Brian Douglas
( @BrianDGLS, website )

An elemental knot. Inspired by Celtic knots and art.


By Raimon Ràfols
( @rrafols, website )

Very very simple voxel engine :)

Son of a Beach

By Xanmia
( @Xanmia, website )

Mouse over water to draw land. Click to export/save island. Drag and drop saved file to load island.


By Felipe Alfonso
( @bitnenfer, website )

Small demo of parallax effect

Paint by Worms

By Nik Coughlin
( @nrknthuk, website )

Clicking anywhere on the canvas spawns a generation of elemental "worms" which compete to paint the canvas by squirming around randomly, affecting the canvas pixels which they pass over according to w…

Dotted Elements

By Peter van der Zee
( @kuvos, website )

Shows the name of all elements and their number in a few thousand individually moving pixels. Can be slow.


By Maxime Euzière
( @MaximeEuziere, website )

A 1kb JavaScript "unpacker" and "unminifier". Paste any minified or RegPacked code on top, and it'll appear beautified on the bottom. Ideal for reverse-engineering your favourite js1k demos!


By Lara
( @literallylara )

Listen to 1500+ digits of π.


By Gabor Bata
( website )

Elementary mental experience based on an episode of the 31st century's most popular TV series: Everybody Loves Hypnotoad.

Rotating Squares

By Siddharth Parmar
( @sidd11parmar, website )

Squares rotating and translating with random speed in 2d Canvas

Funky Fungi

By lsdlive
( @lsdlive )

Fungi emerging from the Mandelbrot Set.

Bubble made of 4000 letters

By LuisQuin
( @LuisQuin9000, website )

These are 4 thousand letters forming a weird bubble with suicidal tendences. The end is nigh.

Element tracer

By Viktor Kovacs
( @kovacsv84, website )

Sphere based ray tracer. Refresh to generate random spheres.

Elemental Forest

By Richard Sudaryono
( @gamehelp16, website )

Enjoy a relaxing walk through an infinitely procedural generated forest.


By Lara
( @literallylara )

When will it awake?


By Maxime Euzière
( @MaximeEuziere, website )

Discover all the glyphs of Unicode 8.0 in this super-long slideshow. Best viewed on Firefox.

Sleeping Dragon

By Jesus Seijas

The skin of the chromatic dragon when is sleeping.

3d shading with points (old commodore style)

By LuisQuin
( @LuisQuin9000, website )

Inspired by a CodePen by Loktar (http://codepen.io/loktar00/pen/zEhDB). Enhanced and prepared to work in 1024b by me.


By Damien Fayol
( website )

A mesmerizing merge of colours.

Energy within

By subzey
( @subzey )

Burning blob and orbiting particles. No interaction, just sit back and enjoy.

Terrain generated with Mid-Point technique

By LuisQuin
( @LuisQuin9000, website )

Inspired by a JSfiddle by Loktar (https://jsfiddle.net/loktar/XDpd3/). Enhanced and prepared to work in 1024b by me.

Recursive tree

By LuisQuin
( @LuisQuin9000, website )

A little experiment with recursive functions in JS. It generates a random tree on the HTML5 Canvas element. Cool or not?

eleMental clock

By Manolopm
( @manolopm )

eleMental clock show a clock where the position of the green balls are the seconds, the red ones the minutes and the blue one the hours.


By Codegolf Team
( website )

Codegolf team is back with a table of isotopes and the decay types for all the chemical elements!

Simplified CustomElement

By Andrea Giammarchi
( @WebReflection, website )

JS1K version of my DOMClass library. CustomElements for everyone.


By Benjamin Grosse

scrolling noise on 2 canvases, put into perspective with css

Supernova 1k

By Standardabweichung Interactive Design
( website )

A visualisation of the 118 known chemical elements, based on the number of electrons per shell.


By Felipe Alfonso
( @bitnenfer )

Marmmodore-1K or Marmmodore-1000 is a

Electric Bullet

By cro

Survive the electric bullet hell! Shoot at the atoms with Z, dodge electrons with Arrows, slow down with Shift, and use I for invincibility.


By Rémi Vansteelandt
( @remvst, website )

Simple chopper game


By Jon Mullins

3d version of a spirograph. Click and drag values to change, click and drag model to rotate. Uses hypotrochoid equations rotated about the z axis. Note some weirdness due to rounding issues when the m…


By Codegolf Team
( website )

The (mandatory) periodic table of chemical elements, including type, name, atomic number, atomic mass and stability for each of the 118 elements!