Claude Sonnet 5 vs GPT-5.6 Sol
Pricing, benchmarks, and use case comparison
Quick take
- •GPT-5.6 Sol leads on 1 of 1 shared benchmarks, including Terminal-Bench 2.1 (88.8% vs 80.4%).
- •Claude Sonnet 5 is meaningfully stronger at cost efficiency (85 vs 55 on our capability index).
- •Claude Sonnet 5 is 40% cheaper on input tokens, which compounds fast on high-volume or agentic workloads.
Specs comparison
| Claude Sonnet 5 | GPT-5.6 Sol | |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Type | Closed source | Closed source |
| Context window | ✓1M | Not announced |
| Input / 1M tokens | ✓$3.00 | $5.00 |
| Output / 1M tokens | $15.00 | $30.00 |
| Release date | 2026-06 | 2026-06 |
Benchmarks
| Benchmark | Claude Sonnet 5 | GPT-5.6 Sol |
|---|---|---|
| SWE-bench Verified | ~85.2% | - |
| Terminal-Bench 2.1 | 80.4% | ✓88.8% |
| SWE-bench Pro | 63.2% | - |
| OSWorld-Verified | 81.2% | - |
| Terminal-Bench 2.1 (Ultra) | - | 91.9% |
| ExploitBench | - | competitive with Mythos Preview |
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 GPT-5.6 Sol if...
- →You are an approved preview partner needing the most capable model for agentic software engineering
- →Complex multi-step tasks that benefit from subagent orchestration (Ultra) or maximum reasoning depth (max)
- →Frontier scientific research, professional knowledge work, or security-sensitive workloads