Claude Sonnet 5 vs DeepSeek V3
Pricing, benchmarks, and use case comparison
Quick take
- •Claude Sonnet 5 is meaningfully stronger at multimodal (85 vs 10 on our capability index).
- •DeepSeek V3 is open-weights (free to self-host); Claude Sonnet 5 is paid API only.
- •Claude Sonnet 5 has a 1M context window vs 128K tokens - better for whole-repo or long-document work.
Specs comparison
| Claude Sonnet 5 | DeepSeek V3 | |
|---|---|---|
| Provider | Anthropic | DeepSeek |
| Type | Closed source | Open source |
| Context window | ✓1M | 128K tokens |
| Input / 1M tokens | $3.00 | ✓Free (self-host) |
| Output / 1M tokens | $15.00 | Free (self-host) |
| Release date | 2026-06 | 2024-12 |
Benchmarks
| Benchmark | Claude Sonnet 5 | DeepSeek V3 |
|---|---|---|
| SWE-bench Verified | ~85.2% | - |
| Terminal-Bench 2.1 | 80.4% | - |
| SWE-bench Pro | 63.2% | - |
| OSWorld-Verified | 81.2% | - |
| Pre-training scale | - | ~15T tokens |
Scores sourced from official provider release posts and independent benchmark aggregators.
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 V3 if...
- →You want a proven, stable open model with broad ecosystem support
- →You need to self-host or fine-tune without licensing friction
- →Cost is critical and you don't need V4's 1M context or top scores
- →You want reproducible open-weight behavior pinned to a known version