AI Glossary
What is GRPO?
Overview
GRPO, or Group Relative Policy Optimization, is a reinforcement-learning method that trains a model by comparing rewards across a group of sampled responses instead of relying on a separate value model. It matters because it can make reasoning-model post-training more memory-efficient while still encouraging responses that score better on verifiable tasks.
Why it matters
GRPO has become a practical post-training technique for improving reasoning behavior in language and multimodal models.
Where it appears in AI research
- Reasoning model technical reports
- Reinforcement learning post-training
- Verifiable reward experiments
- Open-weight model training recipes