Claude Haiku 4.5 Reasoning vs DeepSeek-R1 Chat: which model should you choose?
We compared Claude Haiku 4.5 Reasoning and DeepSeek-R1 Chat on price, context window and 12 benchmarks. DeepSeek-R1 Chat has the stronger average benchmark score; DeepSeek-R1 Chat 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
DeepSeek-R1 Chat
DeepSeek-R1 Chat is a multimodal model from DeepSeek. It offers a 400,000-token context window, costs $5.62 per million input tokens and $21.49 per million output tokens, and averages 82.4 across the index's benchmark suite.
- Input
- $5.62 / 1M
- Output
- $21.49 / 1M
- Context
- 400,000
- Avg score
- 82.4
- Open weights
- Yes
Specification comparison
| Spec | Claude Haiku 4.5 Reasoning | DeepSeek-R1 Chat | Edge |
|---|---|---|---|
| Input price / 1M | $15.11 | $5.62 | B |
| Output price / 1M | $70.05 | $21.49 | B |
| Context window | 128,000 | 400,000 | B |
| Max output | 128,000 | 128,000 | Tie |
| Average score | 81.4 | 82.4 | B |
| Arena Elo | 1444.2 | 1433.3 | A |
| Open weights | No | Yes | B |
Benchmark comparison
Claude Haiku 4.5 Reasoning wins 6, DeepSeek-R1 Chat wins 5, and 1 benchmarks are tied. The table shows the modelled score for each model and the gap.
| Benchmark | Claude Haiku 4.5 Reasoning | DeepSeek-R1 Chat | Gap | Winner |
|---|---|---|---|---|
| MMLU-Pro | 83.4 | 83.4 | 0.0 | Tie |
| GPQA Diamond | 74.6 | 80.0 | 5.4 | DeepSeek-R1 Chat |
| SWE-bench Verified | 69.6 | 71.7 | 2.1 | DeepSeek-R1 Chat |
| HumanEval | 88.7 | 84.9 | 3.8 | Claude Haiku 4.5 Reasoning |
| MATH-500 | 85.8 | 89.1 | 3.3 | DeepSeek-R1 Chat |
| AIME 2025 | 79.0 | 78.6 | 0.4 | Claude Haiku 4.5 Reasoning |
| LiveCodeBench | 73.8 | 79.3 | 5.5 | DeepSeek-R1 Chat |
| IFEval | 89.9 | 89.5 | 0.4 | Claude Haiku 4.5 Reasoning |
| TruthfulQA | 82.5 | 82.3 | 0.2 | Claude Haiku 4.5 Reasoning |
| HellaSwag | 90.9 | 90.6 | 0.3 | Claude Haiku 4.5 Reasoning |
| MMMU | 76.7 | 77.1 | 0.4 | DeepSeek-R1 Chat |
| Arena Elo | 1444.2 | 1433.3 | 10.9 | 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 DeepSeek-R1 Chat costs about $9.59. DeepSeek-R1 Chat is roughly 67% 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.
DeepSeek-R1 Chat has the larger context window at 400,000 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 6, DeepSeek-R1 Chat wins 5, and 1 are tied. On the index average, DeepSeek-R1 Chat leads Claude Haiku 4.5 Reasoning by 1.0 points (82.4 versus 81.4).
The price picture favours DeepSeek-R1 Chat. The context picture favours DeepSeek-R1 Chat. 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 DeepSeek-R1 Chat for quality-sensitive work, and check whether its price holds at your expected volume before committing.
Choose Claude Haiku 4.5 Reasoning if
- You prefer Anthropic's tooling or already use it.
Choose DeepSeek-R1 Chat 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 400,000-token context window.
- You need open weights for self-hosting or fine-tuning.
FAQ
Is Claude Haiku 4.5 Reasoning better than DeepSeek-R1 Chat?
On the index average, DeepSeek-R1 Chat leads Claude Haiku 4.5 Reasoning by 1.0 points (82.4 versus 81.4). The better choice depends on price, context and your task. Claude Haiku 4.5 Reasoning wins 6 benchmarks, DeepSeek-R1 Chat wins 5.
Which is cheaper, Claude Haiku 4.5 Reasoning or DeepSeek-R1 Chat?
DeepSeek-R1 Chat is cheaper on a blended 3:1 basis at about $9.59 per million tokens, versus $28.84 for Claude Haiku 4.5 Reasoning.
Which has the larger context window?
DeepSeek-R1 Chat has the larger context window at 400,000 tokens. Claude Haiku 4.5 Reasoning has 128,000 tokens.
Are these models open weights?
Claude Haiku 4.5 Reasoning is proprietary; DeepSeek-R1 Chat is open weights.
Which should I choose for production?
If you need a single default, start with DeepSeek-R1 Chat for quality-sensitive work, and check whether its price holds at your expected volume before committing.