OpenAI releases o3-mini, an AI reasoning model great for science, math and coding

OpenAI has released o3-mini, a new free STEM-focused reasoning model, in direct response to competitive pressure from Chinese AI company DeepSeek.

The big picture: OpenAI’s latest model release represents a significant shift in its strategy by making advanced reasoning capabilities freely available to all users for the first time.

• The model shows particular strength in science, math, and coding applications while operating with lower costs and latency than its predecessor
• Users can select from three different reasoning effort levels to balance speed and accuracy
• The medium version of o3-mini delivers responses 24% faster than o1-mini, reducing average response time from 10.16 to 7.7 seconds

Performance improvements: The new model demonstrates substantial gains in both accuracy and user satisfaction compared to previous versions.

• Testing revealed a 39% reduction in major errors compared to o1-mini
• Users preferred o3-mini’s responses 56% of the time over its predecessor
• The model includes a prototype search function that provides up-to-date answers with web source links

Accessibility and usage limits: OpenAI has implemented a tiered access system that balances availability with usage restrictions.

• Paid subscribers (Plus, Team, and Pro tiers) will see o3-mini replace o1-mini in their model options
• Plus and Team subscribers can send 150 messages per day, up from the previous 50-message limit
• Free users can access the model through a “Reason” option in the ChatGPT interface

Safety and limitations: OpenAI has conducted extensive testing while acknowledging the model’s current constraints.

• Safety evaluations included testing for potential misuse in areas like chemical and biological weapons
• The model’s persuasion capabilities were found to be comparable to human-written text
• Testing revealed poor performance in machine learning research capabilities and scored 0% on automating OpenAI research engineer tasks
• Training utilized both public data and custom datasets with rigorous filtering for quality and risk mitigation

Strategic implications: This release signals OpenAI’s commitment to maintaining market leadership while democratizing access to AI capabilities, though questions remain about the long-term impact of making advanced AI models freely available and how competitors will respond to this move.