Compare / head-to-head
Claude Sonnet 5vsGPT-5.1
Claude Sonnet 5 leads 2 of 3 shared benchmarks. GPT-5.1 is 1.1x cheaper per token. Claude Sonnet 5 has the larger context window (1M tokens).
Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.
Shared benchmarks
2 – 1
Claude Sonnet 5 leads
Cheaper per token
GPT-5.1
1.1x cheaper, input + output
Larger context
Claude Sonnet 5
1M tokens
Provider uptime (30d)
100% · 95.5679%
Anthropic · OpenAI
Claude Sonnet 5
Anthropic · released 2026-06-30
textvision
Quality
Benchmark matrix
3 shared · 5 only Claude Sonnet 5 · 3 only GPT-5.1| Benchmark | Claude Sonnet 5 | GPT-5.1 | Δ | Edge |
|---|---|---|---|---|
| Reported by both · 3 | ||||
| GPQA Diamond | 90.5% ↗epoch | 87.6% ↗epoch | +2.9 pt | Claude Sonnet 5 |
| OTIS Mock AIME 2024-2025 (Epoch AI run) | 94.7% ↗epoch | 88.6% ↗epoch | +6.1 pt | Claude Sonnet 5 |
| SimpleQA Verified | 33.7% ↗epoch | 48% ↗epoch | -14.3 pt | GPT-5.1 |
| Only Claude Sonnet 5 reports · 5 | ||||
| SWE-bench Verified | 85.2% ↗ | not reported | — | — |
| Humanity's Last Exam (no tools) | 43.2% ↗ | not reported | — | — |
| FrontierMath Tier 4 v2 (Epoch AI run) | 29.3% ↗epoch | not reported | — | — |
| FrontierMath Tiers 1-3 v2 (Epoch AI run) | 65.6% ↗epoch | not reported | — | — |
| Humanity's Last Exam (with tools) | 57.4% ↗ | not reported | — | — |
| Only GPT-5.1 reports · 3 | ||||
| AIME 2025 | not reported | 94.2% ↗matharena ⚠ | — | — |
| LMArena Elo | not reported | 1422.6 ↗ | — | — |
| SWE-bench Verified (Epoch AI run) | not reported | 68% ↗epoch | — | — |
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is Claude Sonnet 5 minus GPT-5.1 in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing
Side by side
Official pricing pages and model cards| Spec | Claude Sonnet 5 | GPT-5.1 | Edge |
|---|---|---|---|
| Context window | 1M tokens | 400K tokens | Claude Sonnet 5 |
| Max output | 128K tokens | 128K tokens | Tie |
| Input price / 1M | $2 ↗ | $1.25 ↗ | GPT-5.1 |
| Output price / 1M | $10 ↗ | $10 ↗ | Tie |
| Cached input / 1M | $0.2 ↗ | $0.125 ↗ | GPT-5.1 |
| Input + output / 1M Lower is cheaper. List prices; batch, tool and regional fees excluded. | $12 | $11.25 | GPT-5.1 |
| Modalities | text · vision | text · vision | Tie |
| Released | 2026-06-30 | 2025-11-13 | — |
| Cited benchmark scores | 8 | 6 | — |
Reliability
Provider status
Last 60 days · refreshed daily on this page · live on /statusMore matchups
Claude Sonnet 5 vs …
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GPT-5.1 vs …
Models sharing the most benchmarksBuilt by Respan
Which one wins on your data?
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