Claude Sonnet 4.5 vs DeepSeek R1
Claude Sonnet 4.5 (2025) and DeepSeek R1 (2025) are frontier-tier reasoning models from Anthropic and DeepSeek. Claude Sonnet 4.5 ships a 200k-token context window, while DeepSeek R1 ships a 128k-token context window. On SWE-bench Verified, Claude Sonnet 4.5 leads by 28 pts. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.
Claude Sonnet 4.5 is safer overall; choose DeepSeek R1 when coding workflow support matters.
Decision scorecard
Local evidence first| Signal | Claude Sonnet 4.5 | DeepSeek R1 |
|---|---|---|
| Best for | reasoning-heavy apps, multimodal apps, and tool-calling agents | reasoning-heavy apps and provider-routed production |
| Decision fit | Coding, RAG, and Agents | Coding, RAG, and Agents |
| Context window | 200k | 128k |
| Cheapest output | $15/1M tokens | $0.30/1M tokens |
| Provider routes | 8 tracked | 14 tracked |
| Shared benchmarks | SWE-bench Verified leader | 2 rows |
Decision tradeoffs
- Claude Sonnet 4.5 holds a shared-benchmark lead on SWE-bench Verified, ahead by 28 points.
- Claude Sonnet 4.5 has the larger context window for long prompts, retrieval packs, or transcript analysis.
- Claude Sonnet 4.5 uniquely exposes Vision, Multimodal, and Function calling in local model data.
- Local decision data tags Claude Sonnet 4.5 for Coding, RAG, and Agents.
- DeepSeek R1 has the lower cheapest tracked output price at $0.30/1M tokens.
- DeepSeek R1 has broader tracked provider coverage for fallback and procurement flexibility.
- DeepSeek R1 uniquely exposes Code execution in local model data.
- Local decision data tags DeepSeek R1 for Coding, RAG, and Agents.
Monthly cost at traffic
Estimate token spend from the cheapest tracked input and output route or tier on this page.
Claude Sonnet 4.5
$6,150
Cheapest tracked route/tier: Microsoft Foundry
DeepSeek R1
$155
Cheapest tracked route/tier: Bitdeer AI
Estimated monthly gap: $5,995. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.
Switch friction
- Provider overlap exists on OpenRouter, Microsoft Foundry, and AWS Bedrock; start route-level A/B tests there.
- DeepSeek R1 is $14.70/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
- Check replacement coverage for Vision, Multimodal, and Function calling before moving production traffic.
- DeepSeek R1 adds Code execution in local capability data.
- Provider overlap exists on Microsoft Foundry, GCP Vertex AI, and AWS Bedrock; start route-level A/B tests there.
- Claude Sonnet 4.5 is $14.70/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
- Check replacement coverage for Code execution before moving production traffic.
- Claude Sonnet 4.5 adds Vision, Multimodal, and Function calling in local capability data.
Specs
| Specification | ||
|---|---|---|
| Released | 2025-09-29 | 2025-01-20 |
| Context window | 200k | 128k |
| Parameters | — | 671B, 37B Active |
| Architecture | decoder only | decoder only |
| License | Proprietary | MIT(OSI) |
| Openness | Proprietary | Open source |
| Commercial use | Commercial use with conditions | Commercial use allowed |
| Knowledge cutoff | 2025-12 | 2023-12 |
Pricing and availability
| Pricing attribute | Claude Sonnet 4.5 | DeepSeek R1 |
|---|---|---|
| Input price |
| $0.10/1M tokens |
| Output price |
| $0.30/1M tokens |
| Providers |
Capabilities
| Capability | Claude Sonnet 4.5 | DeepSeek R1 |
|---|---|---|
| Vision | Yes | No |
| Multimodal | Yes | No |
| Reasoning | Yes | Yes |
| Function calling | Yes | No |
| Tool use | Yes | No |
| Structured outputs | Yes | Yes |
| Code execution | No | Yes |
| IDE integration | No | No |
| Computer use | No | No |
| Parallel agents | No | No |
Benchmarks
| Benchmark | Claude Sonnet 4.5 | DeepSeek R1 |
|---|---|---|
| SWE-bench Verified | 77.2 | 49.2 |
| Google-Proof Q&A | 83.4 | 71.5 |
Deep dive
On shared benchmark coverage, SWE-bench Verified has Claude Sonnet 4.5 at 77.2 and DeepSeek R1 at 49.2, with Claude Sonnet 4.5 ahead by 28 points; Google-Proof Q&A has Claude Sonnet 4.5 at 83.4 and DeepSeek R1 at 71.5, with Claude Sonnet 4.5 ahead by 11.9 points. The largest visible gap is 28 points on SWE-bench Verified, which matters most when that benchmark mirrors your workload. Treat isolated benchmark wins as directional, because provider routing, prompt style, and tool access can move real application results.
The capability footprint differs most on vision: Claude Sonnet 4.5, multimodal input: Claude Sonnet 4.5, function calling: Claude Sonnet 4.5, tool use: Claude Sonnet 4.5, and code execution: DeepSeek R1. Both models share reasoning mode and structured outputs, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.
For cost, Claude Sonnet 4.5 lists tiered pricing: 0-200,001t is $3/1M input and $15/1M output; 200,001t+ is $6/1M input and $22.50/1M output, while DeepSeek R1 lists $0.10/1M input and $0.30/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts DeepSeek R1 lower by about $6.44 per million blended tokens. For tiered rows, this cheapest-track view can understate interactive or fast-lane spend, so compare the tier you will actually use. Availability is 8 providers versus 14, so concentration risk also matters.
Choose Claude Sonnet 4.5 when long-context analysis and larger context windows are central to the workload. Choose DeepSeek R1 when coding workflow support, lower input-token cost, and broader provider choice are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship.
FAQ
Which has a larger context window, Claude Sonnet 4.5 or DeepSeek R1?
Claude Sonnet 4.5 supports 200k tokens, while DeepSeek R1 supports 128k tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.
Which is cheaper, Claude Sonnet 4.5 or DeepSeek R1?
Claude Sonnet 4.5 lists tiered pricing: 0-200,001t is $3/1M input and $15/1M output; 200,001t+ is $6/1M input and $22.50/1M output. DeepSeek R1 lists $0.10/1M input and $0.30/1M output tokens on the cheapest tracked provider. Compare the tier you will actually use; cheap async pricing can overstate savings for interactive workflows. Provider discounts or batch pricing can still change the final bill.
Is Claude Sonnet 4.5 or DeepSeek R1 open source?
Claude Sonnet 4.5 is listed under Proprietary. DeepSeek R1 is listed under MIT. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.
Which is better for vision, Claude Sonnet 4.5 or DeepSeek R1?
Claude Sonnet 4.5 has the clearer documented vision signal in this comparison. If vision is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Which is better for multimodal input, Claude Sonnet 4.5 or DeepSeek R1?
Claude Sonnet 4.5 has the clearer documented multimodal input signal in this comparison. If multimodal input is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Where can I run Claude Sonnet 4.5 and DeepSeek R1?
Claude Sonnet 4.5 is available on Microsoft Foundry, Anthropic, Snowflake Cortex, GCP Vertex AI, and AWS Bedrock. DeepSeek R1 is available on DeepSeek Platform, OpenRouter, Together AI, Fireworks AI, and NVIDIA NIM. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-05-22. Data sourced from public model cards and provider documentation.