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Gravity Simulator
MrEconomical (1399)

this is a gravity simulator

I thought it would be cool to be able to mess around with gravity and experiment, so I made this simple gravity simulator.


  • Scientifically accurate (for the most part)
  • Interactive object placement and deletion
  • Customizable gravity values and object masses
  • Tick warping
  • Hotkeys (G for gravity spot, O for object, and X for delete)

A few notes:

The objects do not collide with each other and instead pass through each other, and the gravity spots are fixed (not influenced by gravity)

Simulation might be a bit buggy on very small screens because of how the scaling works but for the most part it's fine

If you zoom out a ton it's laggy

Zavexeon (890)

Why is everyone better at programming than me lol.

emotionbot (5)

@Zavexeon welcome to the jungle!

DJWang (941)

I made a black hole

PowerCoder (188)

If you hold an object to two grey spots you'll get a perfect orbit. (Really nice and satisfying by the way. Great job!)

Zexogon (592)

Is this dead yet?

DJWang (941)

how do control the number of mass

MrEconomical (1399)

@DJWang open up the settings on the bottom of the toolbar


When I set the gravity to max, I created an orbit where the blue ball goes around in an oval pattern, but then it moves just enough that it creates a spirograph!! Imagine that? Having a year within a year :D

PantheraLeo04 (1)

@JORDANSISNEY Most planets' orbits actually do rotate like how you described.

AtticusKuhn (165)

It is like universe sandbox.

sugarfi (148)

Nice. You should also look into matter.js

Andi_Chin (134)

my planet is just gaining infinite energy

CodeABC123 (78)

Why don’t you take this to the next level and make a quantum simulator?

UncleSamIs234 (0)

This looks super cool it doesn't look like you used HTML it's just so cool.

PizzaRules668 (7)

You should try to make a 3D version

WaffleCode (2)

Mine won't load. =[ Probably my AWFUL school connection

sycrepl (5)

yo i just made a binary figure 8 :O

MatthewDoan1 (252)

Nice. Can you add an option to adjust the length of the trail? I want to see the lengths of my comets!

RohilPatel (351)

If only you could eat gravity

shreykeny (5)

Very cool @MrEconomical! Nice hack!

PS : Did anyone else try recreating the ReactJS logo inside this? 😛

realGNOM (0)


LiamDonohue (60)

this is very satisfying