Best free MuJoCo alternatives

✦ WhyA MuJoCo alternative — Open platform of world foundation models, datasets and tools for physical AI.

• Open platform of world foundation models, datasets and tools for physical AI
• Cosmos Predict, Transfer and Reason models on Hugging Face
• Generates and reasons over synthetic robotics and driving video
• Open weights under NVIDIA open license

✦ WhyA MuJoCo alternative — Open PyTorch library for training real-world robot control policies (ACT, Diffusion Policy, VLA models).

• Open PyTorch library for training real-world robot control policies (ACT, Diffusion Policy, VLA models)
• Direct integration with Hugging Face Hub for sharing datasets and pretrained robot policies
• Works with low-cost hobbyist robot arms (SO-100/101), not just simulation

✦ WhyA MuJoCo alternative — Open, Apache-2.0-licensed vision-language-action foundation model for generalist humanoid robots (GR00T N1.7).

• Open, Apache-2.0-licensed vision-language-action foundation model for generalist humanoid robots (GR00T N1.7)
• Opened to all developers worldwide Apr 2026 (previously partner-only), running on DGX Cloud
• Full pipeline: pretrained model + simulation fine-tuning + deployment tools, not just a research checkpoint

✦ WhyA MuJoCo alternative — Unified multi-physics simulation engine plus photorealistic renderer for robotics/embodied-AI training, fully open source.

• Unified multi-physics simulation engine plus photorealistic renderer for robotics/embodied-AI training, fully open source
• 30,000+ GitHub stars, actively updated as recently as Aug 2026
• Pythonic API designed to be dramatically faster than prior simulators for RL/robot-policy training

✦ WhyA MuJoCo alternative — Open-source weights and code for pi0, pi0-FAST and pi0.5 vision-language-action models.

• Open-source weights and code for pi0, pi0-FAST and pi0.5 vision-language-action models
• Fine-tuning recipes for new robots and tasks
• Apache-2.0

✦ WhyA MuJoCo alternative — GPU-accelerated framework for robot reinforcement and imitation learning on Isaac Sim.

• GPU-accelerated framework for robot reinforcement and imitation learning on Isaac Sim
• Ready environments for humanoids, manipulators and legged robots
• BSD-3-Clause open source

✦ WhyA MuJoCo alternative — Open Qwen3.x family from phone-sized to multi-trillion-parameter MoE, Apache 2.0.

• Open Qwen3.x family from phone-sized to multi-trillion-parameter MoE, Apache 2.0
• Qwen3.6 mid-size models suit agentic coding on one high-memory machine
• Small Qwen3.5 sizes run on phones and laptops
• Free weights on Hugging Face and ModelScope

✦ WhyA MuJoCo alternative — DeepSeek V4-Pro and V4-Flash open-weight MoE models, MIT-licensed.

• DeepSeek V4-Pro and V4-Flash open-weight MoE models, MIT-licensed
• Very long context with reasoning and non-reasoning modes
• Successors to the V3 and R1 lines
• Free weights plus free web chat

✦ WhyA MuJoCo alternative — Open-weight Mistral Medium 3.5, Small 4 and Large 3 general models.

• Open-weight Mistral Medium 3.5, Small 4 and Large 3 general models
• Devstral for coding agents and Magistral for visible reasoning
• Voxtral open-weights speech models for transcription and voice agents