Rapier physics engine
Shares rank 5 of 7 physics engines by recommenders
Free open-source physics engine that people recommend for simulating physics in the browser through WebAssembly, and as a newer option to Bullet.
Free open-source physics engine that people recommend for simulating physics in the browser through WebAssembly, and as a newer option to Bullet.
6 people gave an opinion
- recommend it
- 6
- criticize it
- 0
- approval share
- 100%
Recommended in 4 of 13 months
- November 2025: not recommended
- December 2025: recommended
- January 2026: not recommended
- February 2026: recommended
- March 2026: not recommended
- April 2026: not recommended
- May 2026: not recommended
- June 2026: not recommended
- July 2026: recommended
- August 2026: not recommended
- September 2026: recommended
- October 2026: not recommended
- November 2026: not recommended (month in progress)
Why it doesn’t carry the badge
- 6 people recommend itNeeds 10 or more, not met.
- Nobody criticizes itNeeds 2 to 1 or better, met.
- Recommended in 4 of 13 monthsNeeds 4 or more, met.
The same three rules apply to every product, and the badge can’t be bought. How the badge works
What people say about it
The reasons people give, with the number of comments that give each one. Open a reason to read what they said.
Why people recommend it
Each mark is one comment
Runs physics in the browser
“rigid body physics engines in wasm workers like rapier is feasible now”
Comment from 6 Jul 2026 in “Show HN: Homegames. An open-source game platform I've been making for 8 years” “the cool kids now prefer Rapier for physics in the browser”
Comment from 9 Sep 2026 in “I tested 10 model/harness combinations on the same Three.js task” Preferred over Bullet
“i love that we went from bullet being the only real option”
Comment from 1 Jul 2026 in “Announcing Box3D :: Box2D” “the cool kids now prefer Rapier for physics in the browser”
Comment from 9 Sep 2026 in “I tested 10 model/harness combinations on the same Three.js task”
Other physics engines people recommend
The four most recommended other physics engines, with the same counts for each, so you can compare like for like. The tick on each bar marks the 2 to 1 line the badge needs.
| Product | Recommend | Criticize | Approval | Months | Owned | Badge |
|---|---|---|---|---|---|---|
| Box3D | 14 | 0 | 100% | 1 | — | — |
| Box2D | 12 | 1 | 92% | 1 | — | — |
| MuJoCo | 10 | 0 | 100% | 6 | — | Approved |
| Jolt Physics | 9 | 2 | 82% | 5 | — | — |
| Rapier physics engineThis page | 6 | 0 | 100% | 4 | — | — |
What people said
5 of the 6 comments that mention it, newest first. Each links to the original comment.
“maybe the most impressive real time soft body simulation”
“the cool kids now prefer Rapier for physics in the browser”
“rigid body physics engines in wasm workers like rapier is feasible now”
“i love that we went from bullet being the only real option”
“once I realised that Threlte had support for Rapier physics”
Counts come from 1,795,640 Hacker News comments, November 2025 to November 2026. How we count. Report a mistake.