o3 vs o3 Mini
o3 (2025) and o3 Mini (2025) are frontier-tier reasoning models from OpenAI. o3 ships a 128K-token context window, while o3 Mini ships a not-yet-sourced context window. On Google-Proof Q&A, o3 leads by 8 pts. On pricing, o3 costs $1/1M input tokens versus $1.1/1M for the alternative. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit. It focuses on practical selection signals rather than broad model-family marketing.
Pick o3 for reasoning; o3 Mini is better when coding workflow support matters more.
Specs
Pricing and availability
| o3 | o3 Mini | |
|---|---|---|
| Input price | $1/1M tokens | $1.1/1M tokens |
| Output price | $4/1M tokens | $4.4/1M tokens |
| Providers |
Capabilities
| o3 | o3 Mini | |
|---|---|---|
| Vision | ||
| Multimodal | ||
| Reasoning | ||
| Function calling | ||
| Tool use | ||
| Structured outputs | ||
| Code execution |
Benchmarks
| Benchmark | o3 | o3 Mini |
|---|---|---|
| Google-Proof Q&A | 87.7 | 79.7 |
| Chatbot Arena | 1412.0 | 1335.0 |
| Aider Polyglot | 81.3 | 60.4 |
Deep dive
On shared benchmark coverage, Google-Proof Q&A has o3 at 87.7 and o3 Mini at 79.7, with o3 ahead by 8 points; Chatbot Arena has o3 at 1412 and o3 Mini at 1335, with o3 ahead by 77 points; Aider Polyglot has o3 at 81.3 and o3 Mini at 60.4, with o3 ahead by 20.9 points. The largest visible gap is 77 points on Chatbot Arena, which matters most when that benchmark mirrors your workload. Treat isolated benchmark wins as directional, because provider routing, prompt style, and tool access can move real application results.
The capability footprint differs most on function calling: o3 Mini and tool use: o3 Mini. Both models share reasoning mode, structured outputs, and code execution, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.
For cost, o3 lists $1/1M input and $4/1M output tokens, while o3 Mini lists $1.1/1M input and $4.4/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts o3 lower by about $0.19 per million blended tokens. Availability is 3 providers versus 3, so concentration risk also matters.
Choose o3 when coding workflow support and lower input-token cost are central to the workload. Choose o3 Mini when coding workflow support are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship.
FAQ
Which is cheaper, o3 or o3 Mini?
o3 is cheaper on tracked token pricing. o3 costs $1/1M input and $4/1M output tokens. o3 Mini costs $1.1/1M input and $4.4/1M output tokens. Provider discounts or batch pricing can still change the final bill.
Is o3 or o3 Mini open source?
o3 is listed under Unknown. o3 Mini is listed under Unknown. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.
Which is better for reasoning mode, o3 or o3 Mini?
Both o3 and o3 Mini expose reasoning mode. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.
Which is better for function calling, o3 or o3 Mini?
o3 Mini has the clearer documented function calling signal in this comparison. If function calling is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Which is better for tool use, o3 or o3 Mini?
o3 Mini has the clearer documented tool use signal in this comparison. If tool use is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Where can I run o3 and o3 Mini?
o3 is available on OpenAI API, OpenRouter, and OpenAI Batch API. o3 Mini is available on OpenRouter, OpenAI Batch API, and Azure OpenAI. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-04-24. Data sourced from public model cards and provider documentation.