How to Get All Bodies in Matter.js World

This guide provides a straightforward explanation of how to access and retrieve all physics bodies currently present in a Matter.js simulation. You will learn the standard, recommended approach using built-in composite methods to find every body—including those within nested groups—as well as the direct property access method for top-level objects.

The Recommended Method: Composite.allBodies()

The most reliable way to get an array of every body in your simulation is using the Matter.Composite.allBodies() method. A Matter.js World is itself a composite object that can contain both individual bodies and other nested composites (such as stacks, ragdolls, or compound mechanisms).

Calling Composite.allBodies() traverses the entire hierarchy of your world and returns a flat array containing every single body:

// Assuming 'engine' is your initialized Matter.js engine instance
const allBodies = Matter.Composite.allBodies(engine.world);

// Iterate through the bodies
allBodies.forEach((body) => {
    console.log(body.id, body.position);
});

The Direct Property Method: world.bodies

If you are certain that you have not added any sub-composites and only added direct bodies to the world using Composite.add(engine.world, body), you can access the array directly via the bodies property on the world object:

const directBodies = engine.world.bodies;

Limitation: This array only holds bodies added directly to the root world composite. If you create bodies inside a Matter.Composites.stack or another custom composite and add that composite to the world, those bodies will not appear in engine.world.bodies. For this reason, Matter.Composite.allBodies(engine.world) is preferred in almost all scenarios.