Claude Haiku 4.5 vs o3 Mini
Claude Haiku 4.5 (2025) and o3 Mini (2025) are frontier reasoning models from Anthropic and OpenAI. Claude Haiku 4.5 ships a 200k-token context window, while o3 Mini ships a not-yet-sourced context window. On pricing, Claude Haiku 4.5 costs $0.8/1M 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.
Claude Haiku 4.5 is safer overall; choose o3 Mini when coding workflow support matters.
Specs
| Released | 2025-10-01 | 2025-03-31 |
| Context window | 200k | — |
| Parameters | — | — |
| Architecture | decoder only | decoder only |
| License | Proprietary | Unknown |
| Knowledge cutoff | 2025-02 | 2025-04 |
Pricing and availability
| Claude Haiku 4.5 | o3 Mini | |
|---|---|---|
| Input price | $0.8/1M tokens | $1.1/1M tokens |
| Output price | $4/1M tokens | $4.4/1M tokens |
| Providers |
Capabilities
| Claude Haiku 4.5 | o3 Mini | |
|---|---|---|
| Vision | ||
| Multimodal | ||
| Reasoning | ||
| Function calling | ||
| Tool use | ||
| Structured outputs | ||
| Code execution |
Benchmarks
No shared benchmark rows are currently sourced for this pair.
Deep dive
The capability footprint differs most on vision: Claude Haiku 4.5, multimodal input: Claude Haiku 4.5, 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, Claude Haiku 4.5 lists $0.8/1M 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 Claude Haiku 4.5 lower by about $0.33 per million blended tokens. Availability is 8 providers versus 3, so concentration risk also matters.
Choose Claude Haiku 4.5 when coding workflow support, lower input-token cost, and broader provider choice 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. This keeps the decision grounded in measurable tradeoffs instead of brand-level assumptions. It also helps separate model capability from provider packaging, which can change cost and latency.
FAQ
Which is cheaper, Claude Haiku 4.5 or o3 Mini?
Claude Haiku 4.5 is cheaper on tracked token pricing. Claude Haiku 4.5 costs $0.8/1M 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 Claude Haiku 4.5 or o3 Mini open source?
Claude Haiku 4.5 is listed under Proprietary. 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 vision, Claude Haiku 4.5 or o3 Mini?
Claude Haiku 4.5 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.
Which is better for multimodal input, Claude Haiku 4.5 or o3 Mini?
Claude Haiku 4.5 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.
Which is better for reasoning mode, Claude Haiku 4.5 or o3 Mini?
o3 Mini has the clearer documented reasoning mode signal in this comparison. If reasoning mode is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Where can I run Claude Haiku 4.5 and o3 Mini?
Claude Haiku 4.5 is available on Microsoft Foundry, Anthropic, Snowflake Cortex, AWS Bedrock, and GCP Vertex AI. o3 Mini is available on OpenRouter, OpenAI Batch API, and Azure OpenAI. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
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Last reviewed: 2026-04-24. Data sourced from public model cards and provider documentation.