Claude Sonnet 5 vs DeepSeek V4
Pricing, benchmarks, and use case comparison
Verdict
Our pick: Claude Sonnet 5Pick Claude Sonnet 5 for a managed, multimodal frontier coder with strong computer-use; pick DeepSeek V4 for open MIT weights, self-hosting, and top-tier reasoning at a fraction of the cost.
Specs comparison
| Claude Sonnet 5 | DeepSeek V4 | |
|---|---|---|
| Provider | Anthropic | DeepSeek |
| Type | Closed source | Open source |
| Context window | 1M | 1M tokens |
| Input / 1M tokens | $3.00 | ✓Free (self-host) |
| Output / 1M tokens | $15.00 | Free (self-host) |
| Release date | 2026-06 | 2026-04 |
Benchmarks
| Benchmark | Claude Sonnet 5 | DeepSeek V4 |
|---|---|---|
| SWE-bench Verified | ✓~85.2% | 80.6% |
| Terminal-Bench 2.1 | 80.4% | - |
| SWE-bench Pro | 63.2% | - |
| OSWorld-Verified | 81.2% | - |
| Math / STEM / Coding (open-model comparison) | - | Best among open models (per DeepSeek) |
Scores sourced from official provider release posts and independent benchmark aggregators.
Capability and benchmarks
Both are strong agentic coders. Sonnet 5 reports ~85.2% SWE-bench Verified, 63.2% SWE-bench Pro, 80.4% Terminal-Bench 2.1, and 81.2% OSWorld-Verified. DeepSeek V4 reports 80.6% SWE-bench Verified (Pro-Max) and leads open models on math and STEM (math 93). Their coding scores are close (Sonnet 92 vs DeepSeek 93), but Sonnet 5 adds real multimodal input (85) and computer-use, while DeepSeek V4 is text-only (multimodal 10).
Price, context, and hosting
This is the core trade-off. DeepSeek V4 is open weight under MIT, free to self-host, with a hosted API around $0.435 input / $0.87 output per 1M and steep cache-hit discounts, plus a 1M-token context. Sonnet 5 is a managed model at $3/$15 ($2/$10 introductory through Aug 31, 2026) with a 1M context. If data control or minimizing per-token cost dominates, DeepSeek wins; if you want a turnkey API with SLAs and multimodality, Sonnet wins. Note DeepSeek V4 is still labeled preview.
Which to pick
- Pick Sonnet 5 for managed agentic coding, image input, computer-use, and enterprise availability across major clouds.
- Pick DeepSeek V4 for self-hosting or data sovereignty, top open-model reasoning and math, and the lowest cost per token, if a preview-status model is acceptable.
Which should you choose?
Choose Claude Sonnet 5 if...
- →You want frontier-adjacent agentic coding but need better cost-efficiency than Opus
- →You are running high-volume agent loops and want strong reasoning per dollar
- →You are already on Sonnet 4.6 and want a same-price capability upgrade
- →You need a 1M context window with fast latency
Choose DeepSeek V4 if...
- →You need a frontier-class open model you can self-host for data control
- →Your workload involves very long documents, codebases, or agent trajectories (up to 1M tokens)
- →You want top-tier agentic coding at a fraction of closed-model cost
- →You need to fine-tune or customize a strong base model