Claude Haiku 4.5 Reasoning vs o3 Vision: which model should you choose?
We compared Claude Haiku 4.5 Reasoning and o3 Vision on price, context window and 12 benchmarks. o3 Vision has the stronger average benchmark score; o3 Vision is cheaper on a blended 3:1 basis.
Claude Haiku 4.5 Reasoning
Claude Haiku 4.5 Reasoning is a multimodal model from Anthropic. It offers a 128,000-token context window, costs $15.11 per million input tokens and $70.05 per million output tokens, and averages 81.4 across the index's benchmark suite.
- Input
- $15.11 / 1M
- Output
- $70.05 / 1M
- Context
- 128,000
- Avg score
- 81.4
- Open weights
- No
o3 Vision
o3 Vision is a multimodal model from OpenAI. It offers a 1,000,000-token context window, costs $15.24 per million input tokens and $65.25 per million output tokens, and averages 81.8 across the index's benchmark suite.
- Input
- $15.24 / 1M
- Output
- $65.25 / 1M
- Context
- 1,000,000
- Avg score
- 81.8
- Open weights
- No
Specification comparison
| Spec | Claude Haiku 4.5 Reasoning | o3 Vision | Edge |
|---|---|---|---|
| Input price / 1M | $15.11 | $15.24 | A |
| Output price / 1M | $70.05 | $65.25 | B |
| Context window | 128,000 | 1,000,000 | B |
| Max output | 128,000 | 8,192 | A |
| Average score | 81.4 | 81.8 | B |
| Arena Elo | 1444.2 | 1436.5 | A |
| Open weights | No | No | Tie |
Benchmark comparison
Claude Haiku 4.5 Reasoning wins 7, o3 Vision wins 5, and 0 benchmarks are tied. The table shows the modelled score for each model and the gap.
| Benchmark | Claude Haiku 4.5 Reasoning | o3 Vision | Gap | Winner |
|---|---|---|---|---|
| MMLU-Pro | 83.4 | 83.6 | 0.2 | o3 Vision |
| GPQA Diamond | 74.6 | 77.8 | 3.2 | o3 Vision |
| SWE-bench Verified | 69.6 | 71.8 | 2.2 | o3 Vision |
| HumanEval | 88.7 | 85.6 | 3.1 | Claude Haiku 4.5 Reasoning |
| MATH-500 | 85.8 | 84.4 | 1.4 | Claude Haiku 4.5 Reasoning |
| AIME 2025 | 79.0 | 82.4 | 3.4 | o3 Vision |
| LiveCodeBench | 73.8 | 73.7 | 0.1 | Claude Haiku 4.5 Reasoning |
| IFEval | 89.9 | 89.3 | 0.6 | Claude Haiku 4.5 Reasoning |
| TruthfulQA | 82.5 | 85.8 | 3.3 | o3 Vision |
| HellaSwag | 90.9 | 89.7 | 1.2 | Claude Haiku 4.5 Reasoning |
| MMMU | 76.7 | 75.7 | 1.0 | Claude Haiku 4.5 Reasoning |
| Arena Elo | 1444.2 | 1436.5 | 7.7 | Claude Haiku 4.5 Reasoning |
Price analysis
On a blended 3:1 input-to-output basis, Claude Haiku 4.5 Reasoning costs about $28.84 per million tokens and o3 Vision costs about $27.74. o3 Vision is roughly 4% cheaper than Claude Haiku 4.5 Reasoning. At high volume, that gap compounds quickly, so price should carry real weight unless the quality difference is decisive.
o3 Vision has the larger context window at 1,000,000 tokens, compared with 128,000 for Claude Haiku 4.5 Reasoning. That matters for long documents, large codebases and multi-step agent traces.
Verdict
Across 12 shared benchmarks, Claude Haiku 4.5 Reasoning wins 7, o3 Vision wins 5, and 0 are tied. On the index average, o3 Vision leads Claude Haiku 4.5 Reasoning by 0.4 points (81.8 versus 81.4).
The price picture favours o3 Vision. The context picture favours o3 Vision. Those two dimensions often matter more than a few benchmark points once a model is good enough for the task.
If you need a single default, start with o3 Vision for quality-sensitive work, and check whether its price holds at your expected volume before committing.
Choose Claude Haiku 4.5 Reasoning if
- You need the larger 128,000-token output limit.
Choose o3 Vision if
- You want the higher average benchmark score in this index.
- Unit cost matters and you want the cheaper blended price.
- You need the larger 1,000,000-token context window.
FAQ
Is Claude Haiku 4.5 Reasoning better than o3 Vision?
On the index average, o3 Vision leads Claude Haiku 4.5 Reasoning by 0.4 points (81.8 versus 81.4). The better choice depends on price, context and your task. Claude Haiku 4.5 Reasoning wins 7 benchmarks, o3 Vision wins 5.
Which is cheaper, Claude Haiku 4.5 Reasoning or o3 Vision?
o3 Vision is cheaper on a blended 3:1 basis at about $27.74 per million tokens, versus $28.84 for Claude Haiku 4.5 Reasoning.
Which has the larger context window?
o3 Vision has the larger context window at 1,000,000 tokens. Claude Haiku 4.5 Reasoning has 128,000 tokens.
Are these models open weights?
Claude Haiku 4.5 Reasoning is proprietary; o3 Vision is proprietary.
Which should I choose for production?
If you need a single default, start with o3 Vision for quality-sensitive work, and check whether its price holds at your expected volume before committing.