OpenAI announced that Deep Research based on ChatGPT o4-mini will be available to all Free users, while everyone else will get higher limits.

OpenAI is introducing a new version of its ChatGPT deep research tool that it says is cheaper to operate. The “lightweight” model is available now to free users, as well as those on several of the company’s paid tiers.

Lightweight o4-mini activates after users hit usage limits, offering shorter but thorough answers with 45.6% accuracy compared to deep research’s 51.5%.