Claude Sonnet 4.5 Pro vs Claude Sonnet 4.5 Turbo: which model should you choose?
We compared Claude Sonnet 4.5 Pro and Claude Sonnet 4.5 Turbo on price, context window and 12 benchmarks. Claude Sonnet 4.5 Pro has the stronger average benchmark score; Claude Sonnet 4.5 Turbo is cheaper on a blended 3:1 basis.
Claude Sonnet 4.5 Pro
Claude Sonnet 4.5 Pro is a frontier model from Anthropic. It offers a 1,000,000-token context window, costs $18.73 per million input tokens and $82.29 per million output tokens, and averages 86.7 across the index's benchmark suite.
- Input
- $18.73 / 1M
- Output
- $82.29 / 1M
- Context
- 1,000,000
- Avg score
- 86.7
- Open weights
- No
Claude Sonnet 4.5 Turbo
Claude Sonnet 4.5 Turbo is a frontier model from Anthropic. It offers a 1,000,000-token context window, costs $18.37 per million input tokens and $81.65 per million output tokens, and averages 85.9 across the index's benchmark suite.
- Input
- $18.37 / 1M
- Output
- $81.65 / 1M
- Context
- 1,000,000
- Avg score
- 85.9
- Open weights
- No
Specification comparison
| Spec | Claude Sonnet 4.5 Pro | Claude Sonnet 4.5 Turbo | Edge |
|---|---|---|---|
| Input price / 1M | $18.73 | $18.37 | B |
| Output price / 1M | $82.29 | $81.65 | B |
| Context window | 1,000,000 | 1,000,000 | Tie |
| Max output | 16,384 | 65,536 | B |
| Average score | 86.7 | 85.9 | A |
| Arena Elo | 1469.0 | 1461.7 | A |
| Open weights | No | No | Tie |
Benchmark comparison
Claude Sonnet 4.5 Pro wins 7, Claude Sonnet 4.5 Turbo wins 5, and 0 benchmarks are tied. The table shows the modelled score for each model and the gap.
| Benchmark | Claude Sonnet 4.5 Pro | Claude Sonnet 4.5 Turbo | Gap | Winner |
|---|---|---|---|---|
| MMLU-Pro | 86.3 | 87.2 | 0.9 | Claude Sonnet 4.5 Turbo |
| GPQA Diamond | 83.1 | 83.7 | 0.6 | Claude Sonnet 4.5 Turbo |
| SWE-bench Verified | 73.9 | 75.2 | 1.3 | Claude Sonnet 4.5 Turbo |
| HumanEval | 92.7 | 90.4 | 2.3 | Claude Sonnet 4.5 Pro |
| MATH-500 | 90.1 | 88.0 | 2.1 | Claude Sonnet 4.5 Pro |
| AIME 2025 | 88.4 | 87.8 | 0.6 | Claude Sonnet 4.5 Pro |
| LiveCodeBench | 81.9 | 78.9 | 3.0 | Claude Sonnet 4.5 Pro |
| IFEval | 94.1 | 91.4 | 2.7 | Claude Sonnet 4.5 Pro |
| TruthfulQA | 86.1 | 87.7 | 1.6 | Claude Sonnet 4.5 Turbo |
| HellaSwag | 92.6 | 93.9 | 1.3 | Claude Sonnet 4.5 Turbo |
| MMMU | 84.5 | 81.1 | 3.4 | Claude Sonnet 4.5 Pro |
| Arena Elo | 1469.0 | 1461.7 | 7.3 | Claude Sonnet 4.5 Pro |
Price analysis
On a blended 3:1 input-to-output basis, Claude Sonnet 4.5 Pro costs about $34.62 per million tokens and Claude Sonnet 4.5 Turbo costs about $34.19. Claude Sonnet 4.5 Turbo is roughly 1% cheaper than Claude Sonnet 4.5 Pro. At high volume, that gap compounds quickly, so price should carry real weight unless the quality difference is decisive.
Both models list a 1,000,000-token context window. That is enough for long documents, large codebases and multi-step agent traces.
Verdict
Across 12 shared benchmarks, Claude Sonnet 4.5 Pro wins 7, Claude Sonnet 4.5 Turbo wins 5, and 0 are tied. On the index average, Claude Sonnet 4.5 Pro leads Claude Sonnet 4.5 Turbo by 0.8 points (86.7 versus 85.9).
The price picture favours Claude Sonnet 4.5 Turbo. 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 Pro for quality-sensitive work and Claude Sonnet 4.5 Turbo for high-volume, well-scoped tasks. Run both on a sample of your own traffic before locking in a choice.
Choose Claude Sonnet 4.5 Pro if
- You want the higher average benchmark score in this index.
Choose Claude Sonnet 4.5 Turbo if
- Unit cost matters and you want the cheaper blended price.
- You need the larger 65,536-token output limit.
FAQ
Is Claude Sonnet 4.5 Pro better than Claude Sonnet 4.5 Turbo?
On the index average, Claude Sonnet 4.5 Pro leads Claude Sonnet 4.5 Turbo by 0.8 points (86.7 versus 85.9). The better choice depends on price, context and your task. Claude Sonnet 4.5 Pro wins 7 benchmarks, Claude Sonnet 4.5 Turbo wins 5.
Which is cheaper, Claude Sonnet 4.5 Pro or Claude Sonnet 4.5 Turbo?
Claude Sonnet 4.5 Turbo is cheaper on a blended 3:1 basis at about $34.19 per million tokens, versus $34.62 for Claude Sonnet 4.5 Pro.
Which has the larger context window?
Both models list a 1,000,000-token context window.
Are these models open weights?
Claude Sonnet 4.5 Pro is proprietary; Claude Sonnet 4.5 Turbo is proprietary.
Which should I choose for production?
If you need a single default, start with Claude Sonnet 4.5 Pro for quality-sensitive work and Claude Sonnet 4.5 Turbo for high-volume, well-scoped tasks. Run both on a sample of your own traffic before locking in a choice.