Claude 3.7 Sonnet Reasoning vs Claude Sonnet 4.5 Vision: which model should you choose?
We compared Claude 3.7 Sonnet Reasoning and Claude Sonnet 4.5 Vision on price, context window and 12 benchmarks. Claude Sonnet 4.5 Vision has the stronger average benchmark score; Claude 3.7 Sonnet Reasoning is cheaper on a blended 3:1 basis.
Claude 3.7 Sonnet Reasoning
Claude 3.7 Sonnet Reasoning is a frontier model from Anthropic. It offers a 128,000-token context window, costs $16.30 per million input tokens and $77.62 per million output tokens, and averages 83.7 across the index's benchmark suite.
- Input
- $16.30 / 1M
- Output
- $77.62 / 1M
- Context
- 128,000
- Avg score
- 83.7
- Open weights
- No
Claude Sonnet 4.5 Vision
Claude Sonnet 4.5 Vision is a frontier model from Anthropic. It offers a 128,000-token context window, costs $16.99 per million input tokens and $82.33 per million output tokens, and averages 83.8 across the index's benchmark suite.
- Input
- $16.99 / 1M
- Output
- $82.33 / 1M
- Context
- 128,000
- Avg score
- 83.8
- Open weights
- No
Specification comparison
| Spec | Claude 3.7 Sonnet Reasoning | Claude Sonnet 4.5 Vision | Edge |
|---|---|---|---|
| Input price / 1M | $16.30 | $16.99 | A |
| Output price / 1M | $77.62 | $82.33 | A |
| Context window | 128,000 | 128,000 | Tie |
| Max output | 128,000 | 16,384 | A |
| Average score | 83.7 | 83.8 | B |
| Arena Elo | 1464.4 | 1447.6 | A |
| Open weights | No | No | Tie |
Benchmark comparison
Claude 3.7 Sonnet Reasoning wins 8, Claude Sonnet 4.5 Vision wins 4, and 0 benchmarks are tied. The table shows the modelled score for each model and the gap.
| Benchmark | Claude 3.7 Sonnet Reasoning | Claude Sonnet 4.5 Vision | Gap | Winner |
|---|---|---|---|---|
| MMLU-Pro | 86.4 | 84.8 | 1.6 | Claude 3.7 Sonnet Reasoning |
| GPQA Diamond | 81.3 | 79.6 | 1.7 | Claude 3.7 Sonnet Reasoning |
| SWE-bench Verified | 71.0 | 73.7 | 2.7 | Claude Sonnet 4.5 Vision |
| HumanEval | 89.2 | 87.0 | 2.2 | Claude 3.7 Sonnet Reasoning |
| MATH-500 | 90.3 | 90.6 | 0.3 | Claude Sonnet 4.5 Vision |
| AIME 2025 | 79.8 | 86.4 | 6.6 | Claude Sonnet 4.5 Vision |
| LiveCodeBench | 79.6 | 76.5 | 3.1 | Claude 3.7 Sonnet Reasoning |
| IFEval | 90.1 | 89.9 | 0.2 | Claude 3.7 Sonnet Reasoning |
| TruthfulQA | 86.2 | 83.7 | 2.5 | Claude 3.7 Sonnet Reasoning |
| HellaSwag | 90.4 | 89.4 | 1.0 | Claude 3.7 Sonnet Reasoning |
| MMMU | 76.5 | 79.7 | 3.2 | Claude Sonnet 4.5 Vision |
| Arena Elo | 1464.4 | 1447.6 | 16.8 | Claude 3.7 Sonnet Reasoning |
Price analysis
On a blended 3:1 input-to-output basis, Claude 3.7 Sonnet Reasoning costs about $31.63 per million tokens and Claude Sonnet 4.5 Vision costs about $33.33. Claude 3.7 Sonnet Reasoning is roughly 5% cheaper than Claude Sonnet 4.5 Vision. At high volume, that gap compounds quickly, so price should carry real weight unless the quality difference is decisive.
Both models list a 128,000-token context window. That is enough for long documents, large codebases and multi-step agent traces.
Verdict
Across 12 shared benchmarks, Claude 3.7 Sonnet Reasoning wins 8, Claude Sonnet 4.5 Vision wins 4, and 0 are tied. On the index average, Claude Sonnet 4.5 Vision leads Claude 3.7 Sonnet Reasoning by 0.1 points (83.8 versus 83.7).
The price picture favours Claude 3.7 Sonnet Reasoning. The context picture is effectively a tie. 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 Claude Sonnet 4.5 Vision for quality-sensitive work and Claude 3.7 Sonnet Reasoning for high-volume, well-scoped tasks. Run both on a sample of your own traffic before locking in a choice.
Choose Claude 3.7 Sonnet Reasoning if
- Unit cost matters and you want the cheaper blended price.
- You need the larger 128,000-token output limit.
Choose Claude Sonnet 4.5 Vision if
- You want the higher average benchmark score in this index.
FAQ
Is Claude 3.7 Sonnet Reasoning better than Claude Sonnet 4.5 Vision?
On the index average, Claude Sonnet 4.5 Vision leads Claude 3.7 Sonnet Reasoning by 0.1 points (83.8 versus 83.7). The better choice depends on price, context and your task. Claude 3.7 Sonnet Reasoning wins 8 benchmarks, Claude Sonnet 4.5 Vision wins 4.
Which is cheaper, Claude 3.7 Sonnet Reasoning or Claude Sonnet 4.5 Vision?
Claude 3.7 Sonnet Reasoning is cheaper on a blended 3:1 basis at about $31.63 per million tokens, versus $33.33 for Claude Sonnet 4.5 Vision.
Which has the larger context window?
Both models list a 128,000-token context window.
Are these models open weights?
Claude 3.7 Sonnet Reasoning is proprietary; Claude Sonnet 4.5 Vision is proprietary.
Which should I choose for production?
If you need a single default, start with Claude Sonnet 4.5 Vision for quality-sensitive work and Claude 3.7 Sonnet Reasoning for high-volume, well-scoped tasks. Run both on a sample of your own traffic before locking in a choice.