Deep Research feature now available to free ChatGPT users

OpenAI has made the Deep Research tool in ChatGPT available to free-tier users.
Access is limited to five uses per month, using a lightweight version based on the o4-mini-model. To activate the feature, users must click the Deep Research button located below the chat input field before submitting a prompt.
The standard version of Deep Research continues to run on OpenAI’s o3 model, which was previously restricted to paid tiers. According to OpenAI:
The lightweight version of deep research is powered by a version of OpenAI o4-mini and is nearly as intelligent as the deep research people already know and love, while being significantly cheaper to serve. Responses will typically be shorter while maintaining the depth and quality you’ve come to expect.

Usage limits by tier
The new lightweight version is now automatically used once paid users exceed their monthly limits with the standard model. ChatGPT users currently have the following Deep Research usage limits:
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- Free – 5 tasks/month using the lightweight version
- Plus & Team – 10 tasks/month using the standard model, plus an additional 15 tasks/month using the lightweight version
- Pro – 125 tasks/month using the standard model, plus an additional 125 tasks/month using the lightweight version
- Enterprise – 10 tasks/month using the standard model
Once Plus, Pro, or Team users reach their monthly limit on the o3-based version, additional tasks will automatically use the o4-mini model until the monthly limit resets.
Limits reset every 30 days. The 30-day period begins the first time a user activates Deep Research, and renews on the same cycle thereafter. Users can check their remaining tasks by hovering over the Deep Research button in the chat window.
Other platforms also offer similar tools. Google provides limited free access to Deep Research in Gemini, while xAI includes a version in Grok, and Perplexity provides a comparable tool in its core product.