Boids
eater.net
Three rules are all a flock of birds needs
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Physics toys, ecosystems and simulations with no win condition. Set the initial state, then watch what the rules do with it. All 18 were opened and written up by hand, and last checked on 29 July 2026.
9 sites
Good within five seconds of loading.
eater.net
Three rules are all a flock of birds needs
playgameoflife.com
Four rules, and cells that build spaceships anyway
pmneila.github.io
Two chemicals, two dials, and every pattern in nature
brm.io
Two dozen physics scenes you can grab and throw about
classic.minecraft.net
The 2009 version of Minecraft, free in a browser tab
hunar4321.github.io
Coloured dots that attract and repel start forming cells
dan-ball.jp
The falling-sand classic, still updated after fifteen years
sandboxels.r74n.com
Falling sand with hundreds of elements and real chemistry
sandspiel.club
Draw with sand, water, fire and plants and step back
5 sites
One quick round, then you can leave.
falstad.com
Build a circuit and watch the electrons move through it
chakazul.github.io
Game of Life made continuous, and it grows creatures
ncase.me
Draw a system of feedback loops and press play
orb.farm
A sealed glass ecosystem that keeps going without you
traffic-simulation.de
Find out why a jam appears when nothing is blocking
3 sites
Five to fifteen minutes of proper attention.
keiwan.itch.io
Build a jointed creature and let it learn to walk
rednuht.org
Random two-wheeled cars, bred over generations, on hills
netlogoweb.org
Hundreds of agent-based models, running in the browser
1 site
Clear your evening. We warned you.
graememcc.co.uk
The original open-source SimCity, rewritten for browsers
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Vibes ignore categories, so these lists mix this one with the other seventeen.
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