o3-mini was released on December 20, 2024 as the cost-efficient tier of the o3 reasoning model family. It continues the pattern established by o1-mini: delivering strong chain-of-thought reasoning on structured domains (mathematics, coding, science) at a fraction of the full model's cost.
The model supports the reasoning_effort parameter, letting you control reasoning depth per request. Low effort for straightforward technical queries conserves tokens and reduces cost; high effort for competition-level problems applies the full reasoning capability. This flexibility lets you use o3-mini as the default for all technical queries rather than maintaining a routing layer.
With a context window of 200K tokens and support for the standard API features, o3-mini handles the same types of requests as full o3. The tradeoff is concentrated in reasoning depth: on the hardest problems, full o3 will produce more thorough analysis.