GPT-5 Pro vs o3 Mini
GPT-5 Pro (2025) and o3 Mini (2025) are frontier reasoning models from OpenAI. GPT-5 Pro ships a 400k-token context window, while o3 Mini ships a 200k-token context window. On pricing, o3 Mini costs $1.10/1M input tokens versus $15/1M for the alternative. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.
o3 Mini is ~1264% cheaper at $1.10/1M; pay for GPT-5 Pro only for coding workflow support.
Decision scorecard
Local evidence first| Signal | GPT-5 Pro | o3 Mini |
|---|---|---|
| Best for | multimodal apps, tool-calling agents, and provider-routed production | reasoning-heavy apps, tool-calling agents, and provider-routed production |
| Decision fit | Coding, RAG, and Agents | Coding, RAG, and Agents |
| Context window | 400k | 200k |
| Cheapest output | $120/1M tokens | $4.40/1M tokens |
| Provider routes | 2 tracked | 4 tracked |
| Shared benchmarks | 0 shared | 0 shared |
Decision tradeoffs
- GPT-5 Pro has the larger context window for long prompts, retrieval packs, or transcript analysis.
- GPT-5 Pro uniquely exposes Vision and Multimodal in local model data.
- Local decision data tags GPT-5 Pro for Coding, RAG, and Agents.
- o3 Mini has the lower cheapest tracked output price at $4.40/1M tokens.
- o3 Mini has broader tracked provider coverage for fallback and procurement flexibility.
- o3 Mini uniquely exposes Reasoning in local model data.
- Local decision data tags o3 Mini for Coding, RAG, and Agents.
Monthly cost at traffic
Estimate token spend from the cheapest tracked input and output route or tier on this page.
GPT-5 Pro
$42,000
Cheapest tracked route/tier: Vercel AI Gateway
o3 Mini
$1,980
Cheapest tracked route/tier: OpenRouter
Estimated monthly gap: $40,020. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.
Switch friction
- Provider overlap exists on OpenRouter and Vercel AI Gateway; start route-level A/B tests there.
- o3 Mini is $116/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
- Check replacement coverage for Vision and Multimodal before moving production traffic.
- o3 Mini adds Reasoning in local capability data.
- Provider overlap exists on Vercel AI Gateway and OpenRouter; start route-level A/B tests there.
- GPT-5 Pro is $116/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
- Check replacement coverage for Reasoning before moving production traffic.
- GPT-5 Pro adds Vision and Multimodal in local capability data.
Specs
Pricing and availability
| Pricing attribute | GPT-5 Pro | o3 Mini |
|---|---|---|
| Input price | $15/1M tokens | $1.10/1M tokens |
| Output price | $120/1M tokens | $4.40/1M tokens |
| Providers |
Capabilities
| Capability | GPT-5 Pro | o3 Mini |
|---|---|---|
| Vision | Yes | No |
| Multimodal | Yes | No |
| Reasoning | No | Yes |
| Function calling | Yes | Yes |
| Tool use | Yes | Yes |
| Structured outputs | Yes | Yes |
| Code execution | Yes | Yes |
| IDE integration | No | No |
| Computer use | No | No |
| Parallel agents | No | No |
Benchmarks
No shared benchmark scores are currently available for this pair.
Deep dive
The capability footprint differs most on vision: GPT-5 Pro, multimodal input: GPT-5 Pro, and reasoning mode: o3 Mini. Both models share function calling, tool use, 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, GPT-5 Pro lists $15/1M input and $120/1M output tokens on the cheapest tracked provider, while o3 Mini lists $1.10/1M input and $4.40/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts o3 Mini lower by about $44.41 per million blended tokens. Availability is 2 providers versus 4, so concentration risk also matters.
Choose GPT-5 Pro when coding workflow support and larger context windows are central to the workload. Choose o3 Mini when coding workflow support, lower input-token cost, and broader provider choice are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship. This keeps the decision grounded in measurable tradeoffs instead of brand-level assumptions.
FAQ
Which has a larger context window, GPT-5 Pro or o3 Mini?
GPT-5 Pro supports 400k tokens, while o3 Mini supports 200k tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.
Which is cheaper, GPT-5 Pro or o3 Mini?
o3 Mini is cheaper on tracked token pricing. GPT-5 Pro costs $15/1M input and $120/1M output tokens. o3 Mini costs $1.10/1M input and $4.40/1M output tokens. Provider discounts or batch pricing can still change the final bill.
Is GPT-5 Pro or o3 Mini open source?
GPT-5 Pro is listed under Proprietary. o3 Mini is listed under Proprietary. 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 vision, GPT-5 Pro or o3 Mini?
GPT-5 Pro has the clearer documented vision signal in this comparison. If vision is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.
Which is better for multimodal input, GPT-5 Pro or o3 Mini?
GPT-5 Pro has the clearer documented multimodal input signal in this comparison. If multimodal input is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Where can I run GPT-5 Pro and o3 Mini?
GPT-5 Pro is available on Vercel AI Gateway and OpenRouter. o3 Mini is available on OpenRouter, Azure OpenAI, OpenAI API, and Vercel AI Gateway. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
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Last reviewed: 2026-06-15. Data sourced from public model cards and provider documentation.