OpenAI o3-mini is now available in ChatGPT and the API.

Pro users will have unlimited access to o3-mini and Plus & Team users will have triple the rate limits (vs o1-mini). Free users can try o3-mini in ChatGPT by selecting the Reason button under the message composer.
All paid users also have the option of selecting ‘o3-mini-high’ in the model picker for a higher-intelligence version that takes a little longer to generate responses.