I have hand-keyframed a lot of bounces over the years, and it is one of those tasks that looks simple and never is. One ball hitting a floor is tedious. A dozen objects colliding and ricocheting off each other is not really something you can keyframe by hand at all, and faking the feel of real physics almost never lands.
So the team built Gravity, a real 2D physics engine that lives inside After Effects. You set up a scene or drop your own layers in, hit play to watch actual physics run in a sandbox, then bake the whole thing into clean, editable keyframes on your timeline. Here is how it works.
This video may reference an older version of Gravity. Features and UI may have changed since recording.
What Gravity is: a real physics engine for After Effects
At its heart, Gravity is very straightforward. It is a physics engine. The panel has two areas: the Playground at the top, where you build and preview a scene, and My Comp on the right, where you bring in your own After Effects composition. You pick or build a scene, watch the physics play out, and then hand the result to After Effects. That is the whole loop, and everything else is just settings layered on top of it.
Gravity is an After Effects plugin, so all of this happens right inside AE. There is no round trip to another app and nothing to export: you open the panel, run the simulation, and the keyframes land on your layers. If you have ever built a bounce by hand, the appeal is immediate, because here the computer does the physics and you keep a fully editable result.
Install Gravity through Filmit Studio
To get Gravity, make an account on Filmit.io, download Filmit Studio (our desktop app), and install Gravity from there. While you are in Filmit Studio you can install and try any of the other plugins too, because everything is included. Then open it in After Effects by going to Window, then Extensions, then Gravity. If it does not appear right away, restart After Effects and it will show up.
Gravity is a paid plugin, but it is included in the Filmit Studio subscription, one price for the whole growing suite rather than a steep fee per plugin, and that subscription is what funds the constant updates and the new tools we keep shipping. It comes with a 7-day free trial that unlocks the entire bundle, not just Gravity, so you can try every plugin before you decide.
The core loop: pick a scene, play, Create Comp
Start in the Playground. At the top you have your composition settings, so set up the comp you want to build. Below that is a library of ready-made scenes. These are just presets, and you can play any of them to see exactly what they do before you commit. There is a good range to start from, with names like Fill Up, Zero G Billiards, Stairs, and Pinball.
Take Fill Up as the simple example. Hit play and the engine runs, in this case for six seconds, dropping objects that pile up and settle the way real objects would. When it looks right, go to the bottom and hit Create Comp. Gravity builds that exact run inside After Effects, and here is the important part: when you click any layer, every one of them is full of keyframes. The simulation is not a video and it is not an expression, it is baked keyframes on every layer, so you can open the graph editor and adjust anything you like.
Pro Tip: If your built comp looks a little choppy, it is almost always a frame rate mismatch, not a problem with the simulation. The physics run smooth, but your After Effects composition may not be set to 60 frames per second. Set the comp to 60fps and it smooths right out.
Shaping the physics: slingshot, bouncy walls, zero-g, air drag
Presets are just a starting point. Load one up and start changing it. Take Zero G Billiards: let it play, then grab any object and choose slingshot to launch it in a direction with real force behind it, so it shoots off and knocks everything else around. Down at the bottom you can make the floor, the walls, and the ceiling bouncy, so objects keep their energy and ricochet instead of dying on impact. You can also toggle zero-g on, which means nothing settles on its own, and with a bouncy room the motion just keeps going.
Duration is yours to set. A run might default to eight seconds, but you can push it to a fifteen second animation and let the whole thing play out longer. If you want objects to eventually come to rest, turn up the air drag, which bleeds energy off over time until everything settles. Between bouncy surfaces, zero-g, slingshots, and air drag, you are really just dialing in how much energy is in the room and where it goes.
You will also see static gray objects in some scenes, sitting in place as obstacles. Right click any of them to make it dynamic, turn its physics off, keep it moving, or slingshot it, so a fixed bumper can become a live object in one click, or a live object can become a bounce board. And if you just want a fresh arrangement, hit the randomize button and Gravity reshuffles the whole scene, which is a fast way to find a layout you like in Stairs or Pinball before you build.
The headline use case: snapshot your own comp
This is the part that makes Gravity more than a sandbox. You can snapshot your own After Effects composition straight into Gravity and run your real layers through the physics engine. The clearest example is animated text. In After Effects, make a new composition and type your name, but do it as individual letter layers rather than one text layer.
Pro Tip: Type text as individual letter layers, not one word on a single text layer. Separate layers each get their own physics and bounce independently, so they collide and scatter. A single text layer stays together as one block, which is the opposite of what you want here.
With your letters as separate layers, head back to Gravity and snapshot the comp. Now your actual letters are in the sandbox. Make the floor and ceiling bouncy, grab a letter and slingshot it so it flies across and hits the next one, and watch them collide and bounce off each other. Because it is zero-g they will keep moving, so either turn up the air drag to let them settle or just pick your moment. When it looks right, hit Apply to Comp and Gravity bakes the entire run back into After Effects as keyframes on each letter. That is how you make physics-based text and layer animations, real collisions and real bounces, without touching the graph editor by hand.
Pro Tip: Click the Advanced button to open Gravity in a larger window. It is the same tool with more room to work, which makes grabbing objects, slingshotting them, and fine tuning a scene much easier than in the docked panel.
Key takeaways
Gravity turns real 2D physics into clean, editable After Effects keyframes, so bounces and collisions look right without hand-keyframing every frame.
Run a simulation in the sandbox, hit Create Comp or Apply to Comp, and every layer lands in After Effects with baked, fully editable keyframes.
Gravity is an AE plugin, so you set up, simulate, and bake without leaving After Effects or exporting anything.
Bring your real composition into the sandbox and run your layers through the physics, which is ideal for text set as individual letters.
Slingshot objects, make walls bouncy, toggle zero-g, extend the duration, and add air drag to control how energy moves and settles.
If a built comp looks choppy, it is a frame rate mismatch, and a 60fps composition renders the simulation smooth.
Get started with Filmit
Gravity installs through Filmit Studio, the desktop app you download from your dashboard to manage every Filmit plugin for After Effects, Premiere Pro, and DaVinci Resolve. It comes with a 7-day free trial that unlocks the whole bundle, and one install puts Gravity in After Effects and keeps it current.
Start a free trial, install Gravity along with any of the other tools, and come build something with us. The team hangs out on Discord for questions, feedback, and to see what you make with real physics.
