MuJoCo vs 
Gymnasium
MuJoCo vs Gymnasium compared for 2026 — features, license, ease of use, performance and which one to choose. The physics engine most robotics research runs on vs The standard interface for reinforcement learning.
Updated regularly · curated by OpenSourceAI.tech
MuJoCo vs Gymnasium at a glance
| Spec | MuJoCo | Gymnasium |
|---|---|---|
| Category | Robotics & embodied AI | Robotics & embodied AI |
| Type | Physics simulator | RL environment API |
| License | Apache-2.0 | MIT |
| Runs locally | Yes | Yes |
| Primary language | C++ | Python |
| Ease of use | Intermediate | Beginner |
| Best for | training control policies before touching real hardware | learning RL, or benchmarking an algorithm against a known baseline |
| GitHub stars | 14.2k | 12.2k |
How MuJoCo and Gymnasium score
| Criterion | MuJoCo | Gymnasium |
|---|---|---|
| Popularity | 3.0 | 3.0 |
| Maintenance | 5.0 | 5.0 |
| Ease of use | 3.5 | 5.0 |
| Privacy | 5.0 | 5.0 |
| License freedom | 5.0 | 5.0 |
Scores are computed automatically from public signals — GitHub stars (popularity), recent commit activity (maintenance), license type (freedom), local-first design (privacy) and onboarding complexity (ease of use). Indicative, not a verdict.
What each one is
MuJoCo
MuJoCo simulates contact-rich dynamics fast and accurately. DeepMind open-sourced it, and it is now the default for reinforcement learning on robots.
- Accurate contact dynamics at very high speed
- Free since DeepMind released it
- The de-facto standard in RL papers
Gymnasium
Gymnasium is the maintained successor to OpenAI Gym: one API that every RL algorithm and environment speaks.
- The interface the whole RL ecosystem implements
- Dozens of environments included
- Actively maintained, unlike the original Gym
Key differences
MuJoCo is physics simulator, while Gymnasium is rL environment API. Their licenses differ (Apache-2.0 vs MIT), which matters if you ship a commercial product. MuJoCo leans more intermediate-friendly, whereas Gymnasium is more suited to beginner users. In short, MuJoCo fits training control policies before touching real hardware, and Gymnasium fits learning RL, or benchmarking an algorithm against a known baseline.
Which should you choose?
Choose MuJoCo for training control policies before touching real hardware. Choose Gymnasium for learning RL, or benchmarking an algorithm against a known baseline.
There is rarely one winner — many setups use both. The right pick depends on your hardware, your team's skills, and whether you value simplicity or control.
Frequently asked questions
Is MuJoCo or Gymnasium easier to use?
Gymnasium is generally the easier of the two to get started with, while MuJoCo rewards more setup with more control.
Are MuJoCo and Gymnasium free?
MuJoCo is free and open source (Apache-2.0), and Gymnasium is free and open source (MIT). Neither charges for the core software.
Can I run MuJoCo and Gymnasium locally?
MuJoCo: yes · Gymnasium: yes. Both can be used without sending your data to a third-party cloud where their setup allows.
MuJoCo vs Gymnasium — which should I pick in 2026?
Choose MuJoCo for training control policies before touching real hardware. Choose Gymnasium for learning RL, or benchmarking an algorithm against a known baseline.
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