Claude Sonnet 4.5 vs DeepSeek R1 (0528)
Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.
Anthropic · Sep 2025
The model that made 30-hour autonomous coding sessions real — 77.2% SWE-bench Verified and a 1M-token context beta at $3/$15.
DeepSeek · May 2025
The open reasoning model that started it all — RL-trained chain-of-thought, MIT licensed, and a research landmark.
The verdict
DeepSeek R1 (0528) wins 2 of the 3 benchmarks these models share, against 1 for Claude Sonnet 4.5. On price the gap is dramatic: DeepSeek R1 (0528) works out roughly 6.3x cheaper per blended million tokens. Claude Sonnet 4.5 also takes 200K of context versus 128K for DeepSeek R1 (0528). And DeepSeek R1 (0528) is open-weights (MIT), so it can be self-hosted — a structural advantage if data control or vendor independence matters.
Benchmark head-to-head 1–2
Specs & pricing
| Claude Sonnet 4.5 | DeepSeek R1 (0528) | |
|---|---|---|
| modhub Index | 65.5 | 67.8 |
| Input price / 1M | $3 | $0.55 |
| Output price / 1M | $15 | $2.19 |
| Context window | 200K | 128K |
| Max output | 64K | 64K |
| Open weights | no | yes (MIT) |
| Reasoning model | yes | yes |
| Multimodal input | text, image | text |
| Knowledge cutoff | Jan 2025 | Mar 2025 |
| Released | Sep 2025 | May 2025 |
| Example monthly cost* | $52.50 | $8.79 |
* 10M input + 1.5M output tokens per month at list prices, no caching. Green = better value on that row.
Frequently asked questions
- Which is better, Claude Sonnet 4.5 or DeepSeek R1 (0528)?
- DeepSeek R1 (0528) wins 2 of the 3 benchmarks these models share, against 1 for Claude Sonnet 4.5. On price the gap is dramatic: DeepSeek R1 (0528) works out roughly 6.3x cheaper per blended million tokens. Claude Sonnet 4.5 also takes 200K of context versus 128K for DeepSeek R1 (0528). And DeepSeek R1 (0528) is open-weights (MIT), so it can be self-hosted — a structural advantage if data control or vendor independence matters.
- Which is cheaper, Claude Sonnet 4.5 or DeepSeek R1 (0528)?
- Claude Sonnet 4.5 costs $3/$15 per million input/output tokens, while DeepSeek R1 (0528) costs $0.55/$2.19. For a typical workload of 10M input and 1.5M output tokens per month, that's $52.50 versus $8.79.
- Which model is better for coding, Claude Sonnet 4.5 or DeepSeek R1 (0528)?
- We don't yet track SWE-bench Verified results for both models; check their individual pages for coding-related scores.