Claude Sonnet 4.5 vs DeepSeek V4 Pro
Claude Sonnet 4.5 (2025) and DeepSeek V4 Pro (2026) are frontier-tier reasoning models from Anthropic and DeepSeek. Claude Sonnet 4.5 ships a 200k-token context window, while DeepSeek V4 Pro ships a 1m-token context window. On MMLU PRO, DeepSeek V4 Pro leads by 1.5 pts. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.
DeepSeek V4 Pro fits 5x more tokens; pick it for long-context work and Claude Sonnet 4.5 for tighter calls.
Decision scorecard
Local evidence first| Signal | Claude Sonnet 4.5 | DeepSeek V4 Pro |
|---|---|---|
| Best for | reasoning-heavy apps, multimodal apps, and tool-calling agents | reasoning-heavy apps, tool-calling agents, and long-context analysis |
| Decision fit | Coding, RAG, and Agents | Coding, RAG, and Agents |
| Context window | 200k | 1m |
| Cheapest output | $15/1M tokens | $0.87/1M tokens |
| Provider routes | 8 tracked | 5 tracked |
| Shared benchmarks | 3 rows | MMLU PRO leader |
Decision tradeoffs
- Claude Sonnet 4.5 has broader tracked provider coverage for fallback and procurement flexibility.
- Claude Sonnet 4.5 uniquely exposes Vision and Multimodal in local model data.
- Local decision data tags Claude Sonnet 4.5 for Coding, RAG, and Agents.
- DeepSeek V4 Pro holds a shared-benchmark lead on MMLU PRO, ahead by 1.5 points.
- DeepSeek V4 Pro has the larger context window for long prompts, retrieval packs, or transcript analysis.
- DeepSeek V4 Pro has the lower cheapest tracked output price at $0.87/1M tokens.
- Local decision data tags DeepSeek V4 Pro 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 V4 Pro
$566
Cheapest tracked route/tier: DeepSeek Platform
Estimated monthly gap: $5,585. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.
Switch friction
- Provider overlap exists on OpenRouter and Vercel AI Gateway; start route-level A/B tests there.
- DeepSeek V4 Pro is $14.13/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
- Check replacement coverage for Vision and Multimodal before moving production traffic.
- Provider overlap exists on OpenRouter and Vercel AI Gateway; start route-level A/B tests there.
- Claude Sonnet 4.5 is $14.13/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
- Claude Sonnet 4.5 adds Vision and Multimodal in local capability data.
Specs
| Specification | ||
|---|---|---|
| Released | 2025-09-29 | 2026-04-24 |
| Context window | 200k | 1m |
| Parameters | — | 1.6T |
| Architecture | decoder only | Mixture of Experts (MoE) with CSA+HCA hybrid attention |
| License | Proprietary | MIT(OSI) |
| Openness | Proprietary | Open source |
| Commercial use | Commercial use with conditions | Commercial use allowed |
| Knowledge cutoff | 2025-12 | - |
Pricing and availability
| Pricing attribute | Claude Sonnet 4.5 | DeepSeek V4 Pro |
|---|---|---|
| Input price |
| $0.43/1M tokens |
| Output price |
| $0.87/1M tokens |
| Providers |
Capabilities
| Capability | Claude Sonnet 4.5 | DeepSeek V4 Pro |
|---|---|---|
| Vision | Yes | No |
| Multimodal | Yes | No |
| Reasoning | Yes | Yes |
| Function calling | Yes | Yes |
| Tool use | Yes | Yes |
| Structured outputs | Yes | Yes |
| Code execution | No | No |
| IDE integration | No | No |
| Computer use | No | No |
| Parallel agents | No | No |
Benchmarks
| Benchmark | Claude Sonnet 4.5 | DeepSeek V4 Pro |
|---|---|---|
| MMLU PRO | 86.0 | 87.5 |
| SWE-bench Verified | 77.2 | 80.6 |
| Google-Proof Q&A | 83.4 | 90.1 |
Deep dive
On shared benchmark coverage, MMLU PRO has Claude Sonnet 4.5 at 86 and DeepSeek V4 Pro at 87.5, with DeepSeek V4 Pro ahead by 1.5 points; SWE-bench Verified has Claude Sonnet 4.5 at 77.2 and DeepSeek V4 Pro at 80.6, with DeepSeek V4 Pro ahead by 3.4 points; Google-Proof Q&A has Claude Sonnet 4.5 at 83.4 and DeepSeek V4 Pro at 90.1, with DeepSeek V4 Pro ahead by 6.7 points. The largest visible gap is 6.7 points on Google-Proof Q&A, 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 and multimodal input: Claude Sonnet 4.5. Both models share reasoning mode, function calling, tool use, 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 V4 Pro lists $0.43/1M input and $0.87/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts DeepSeek V4 Pro lower by about $6.03 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 5, so concentration risk also matters.
Choose Claude Sonnet 4.5 when vision-heavy evaluation and broader provider choice are central to the workload. Choose DeepSeek V4 Pro when long-context analysis, larger context windows, and lower input-token cost 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 V4 Pro?
DeepSeek V4 Pro supports 1m tokens, while Claude Sonnet 4.5 supports 200k 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 V4 Pro?
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 V4 Pro lists $0.43/1M input and $0.87/1M 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 V4 Pro open source?
Claude Sonnet 4.5 is listed under Proprietary. DeepSeek V4 Pro 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 V4 Pro?
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 V4 Pro?
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 V4 Pro?
Claude Sonnet 4.5 is available on Microsoft Foundry, Anthropic, Snowflake Cortex, GCP Vertex AI, and AWS Bedrock. DeepSeek V4 Pro is available on DeepSeek Platform, Fireworks AI, OpenRouter, Vercel AI Gateway, and Novita AI. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-05-31. Data sourced from public model cards and provider documentation.