OpenAI's most powerful reasoning model for complex tasks
OpenAI o3 is OpenAI's dedicated reasoning model, released in January 2026. Unlike GPT-5.4, which is a general-purpose model, o3 is specifically optimized for tasks requiring deep logical reasoning, mathematical proofs, scientific analysis, and complex coding challenges. It uses a chain-of-thought approach with configurable thinking time, allowing users to set how long the model reasons before responding. o3 has achieved remarkable benchmark scores, including 96.7% on the ARC-AGI benchmark and near-perfect scores on graduate-level math problems. The model is available through ChatGPT (Pro tier) and the API, with o3-mini offering a more affordable option for lighter reasoning tasks. It's particularly valuable for STEM education, competitive programming, and research applications.
Available with ChatGPT Pro ($200/mo). API: $10-60/M tokens depending on thinking time.
o3 (Jan 2026)
OpenAI o3 was released to the public, marking its official debut in the AI landscape.
o3 (Jan 2026)
Subscribe to ChatGPT Pro ($200/month)
Select o3 from the model dropdown
Set reasoning effort: low, medium, or high
Enter complex math, science, or coding problems
Review the thinking process and final answer
Use o3-mini for faster, cheaper reasoning tasks
Best For
Advanced reasoning, math, and scientific problem-solving
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No free tier, Pro subscription required
Try OpenAI o3 with No free tier, Pro subscription required and transform your workflow.