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OpenAI ↗Released April 16, 2025

GPT-o3

#2 Arena RankUndisclosed parameters

GPT-o3 ranks in the top 10 on the Arena leaderboard. Context window: 0.2K tokens.

Context

200K

Input

$2.00

Key Specifications

🏆

Arena Rank

#2

📐

Context Window

200K

📥

Input Price

per 1M tokens

$2.00

📤

Output Price

per 1M tokens

$8.00

🧠

Parameters

Undisclosed

🔒

Open Source

No

Best For

Advanced reasoningagentic tasksresearch

About GPT-o3

GPT-o3 is OpenAI's most advanced reasoning model, succeeding o1 as the frontier of deliberative AI. It uses an enhanced chain-of-thought approach where the model spends more compute time 'thinking' before responding, dramatically improving performance on complex STEM, mathematical, and logical reasoning tasks. With a 200K token context window and the ability to use tools during reasoning, o3 represents a significant leap in AI problem-solving capabilities. It achieved state-of-the-art results on the ARC-AGI benchmark, demonstrating near-human performance on novel reasoning challenges. The model is particularly strong at multi-step mathematical proofs, complex code debugging, and scientific analysis where careful step-by-step reasoning is essential. Originally priced at a premium, an 80% price reduction in June 2025 made o3 accessible to a much broader range of developers and applications.

Built byOpenAI↗

Pricing per 1M tokens

Input Tokens

$2.00

Output Tokens

$8.00

Compare GPT-o3

See how GPT-o3 stacks up against other leading AI models

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Frequently Asked Questions

What is GPT-o3?▾
GPT-o3 is OpenAI's most advanced reasoning model, succeeding o1 as the frontier of deliberative AI. It uses an enhanced chain-of-thought approach where the model spends more compute time 'thinking' before responding, dramatically improving performance on complex STEM, mathematical, and logical reasoning tasks. With a 200K token context window and the ability to use tools during reasoning, o3 represents a significant leap in AI problem-solving capabilities. It achieved state-of-the-art results on the ARC-AGI benchmark, demonstrating near-human performance on novel reasoning challenges. The model is particularly strong at multi-step mathematical proofs, complex code debugging, and scientific analysis where careful step-by-step reasoning is essential. Originally priced at a premium, an 80% price reduction in June 2025 made o3 accessible to a much broader range of developers and applications.
How much does GPT-o3 cost?▾
GPT-o3 costs $2.00 per 1M input tokens and $8.00 per 1M output tokens. You pay only for what you use, which keeps costs predictable.
What is GPT-o3's context window?▾
GPT-o3 has a context window of 200K tokens. This determines how much text the model can process in a single request — bigger windows mean longer documents and richer conversation history.
Is GPT-o3 open source?▾
No, GPT-o3 is a proprietary model available through OpenAI's API. You get managed infrastructure, regular updates, and support as part of the package.
What is GPT-o3 best for?▾
GPT-o3 is best suited for: Advanced reasoning, agentic tasks, research. These use cases play to the model's strengths in capability, speed, and cost within OpenAI's lineup.