Published on November 10, 2024

When building interactive 3D experiences, choosing the right physics engine is crucial. Two excellent options for web development are Jolt and Rapier, both available through WASM bindings.

Rapier

Pros:

• Excellent documentation
• Pure Rust, native WASM support
• Smaller bundle size
• Great for 2D and 3D

Cons:

• Fewer advanced features
• Character controllers need work

Jolt

Pros:

• Industry-proven (used in Horizon games)
• Advanced features (vehicles, characters, ragdoll)
• Excellent stability
• Better for complex simulations

Cons:

• Larger bundle size
• Newer to web ecosystem

Performance Comparison

In benchmarks with 1000 dynamic bodies:

Metric	Rapier	Jolt
Step Time	2.1ms	1.8ms
Memory	12MB	18MB
Bundle	350KB	520KB

Recommendation

Choose Rapier for simpler projects, 2D games, or when bundle size matters.

Choose Jolt for complex 3D games, vehicle physics, or when you need advanced character controllers.

Both have excellent React Three Fiber integrations - @react-three/rapier and @react-three/jolt.