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openai/o3-mini
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o3 Mini

OpenAI o3-mini is a cost-efficient language model optimized for STEM reasoning tasks, particularly excelling in science, mathematics, and coding. This model supports the `reasoning_effort` parameter, which can be set to "high", "medium", or "low" to control the thinking time of the model. The default is "medium". OpenRouter also offers the model slug `openai/o3-mini-high` to default the parameter to "high". The model features three adjustable reasoning effort levels and supports key developer capabilities including function calling, structured outputs, and streaming, though it does not include vision processing capabilities. The model demonstrates significant improvements over its predecessor, with expert testers preferring its responses 56% of the time and noting a 39% reduction in major errors on complex questions. With medium reasoning effort settings, o3-mini matches the performance of the larger o1 model on challenging reasoning evaluations like AIME and GPQA, while maintaining lower latency and cost.

1/31/2025
200,000 tokens
#155 Text (Japanese)

Specifications

Modalities

Input
text
file
Output
text

Supported Parameters

max_tokens
response_format
seed
structured_outputs
tool_choice
tools

Max Output Tokens

100,000

Frequently asked questions

Is o3 Mini available on FastMetal?
Not at the moment. GPT-5.6 Sol, from the same lab, is available on the FastMetal API today.
What is the context window of o3 Mini?
200,000 tokens, shared between the prompt and the response.
How does o3 Mini rank?
#155 on the public arena's Japanese board (ELO 1,297). Ranks move as the leaderboard is updated.

Leaderboard

Text
OverallELO: 1,348
#205
JapaneseELO: 1,297
#155
ChineseELO: 1,357
#215
KoreanELO: 1,291
#165
EnglishELO: 1,362
#213
frenchELO: 1,350
#189
germanELO: 1,323
#180
spanishELO: 1,337
#192
russianELO: 1,328
#214
CodingELO: 1,417
#180
MathELO: 1,381
#168
Creative WritingELO: 1,301
#221
Instruction FollowingELO: 1,343
#197
Hard PromptsELO: 1,370
#197
Multi-TurnELO: 1,340
#211