o3

by OpenAI

o3 is a model from OpenAI, released on April 16, 2025. It has a 200K-token context window and can generate up to 100K output tokens. API pricing is $2 per 1M input tokens and $8 per 1M output tokens. It ranks #78 of 220 models by Intelligence Score with a score of 31.

OpenAI's most powerful reasoning model. o3 is a well-rounded and powerful model across domains. It sets a new standard for math, science, coding, and visual reasoning tasks. It also excels at technical writing and instruction-following. Use it to think through multi-step problems that involve analysis across text, code, and images.

Key specs

ProviderOpenAI
Release date2025-04-16
Licenseproprietary
Context window200K tokens
Max output100K tokens
Input price$2 / 1M tokens
Output price$8 / 1M tokens
Intelligence Score31
Coding index14.8

Quick answers

What is the context window of o3?

o3 has a context window of 200K tokens, with a maximum output of 100K tokens per response.

How much does o3 cost?

o3 costs $2 per 1M input tokens and $8 per 1M output tokens through the API.

Is o3 open source?

No. o3 is a proprietary model from OpenAI (proprietary license).

When was o3 released?

OpenAI released o3 on April 16, 2025.

How does o3 compare to Claude Opus 5.5 (Reasoning)?

o3 scores 31 on the Intelligence Score versus 60.5 for Claude Opus 5.5 (Reasoning), the current #1. Input pricing is $2 vs $4 per 1M tokens.

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