token.app › Compare › GPT-5.5 vs Claude Sonnet 5
GPT-5.5 vs Claude Sonnet 5
GPT-5.5 leads on 3 of 4 shared benchmarks. Claude Sonnet 5 is 2.8× cheaper per token on a blended 3:1 basis. GPT-5.5 accepts the larger context window (1.1M).
Head to head
Blended price uses a 3:1 input:output mix
| GPT-5.5 | Claude Sonnet 5 | |
|---|---|---|
| Provider | OpenAI | Anthropic |
| Input $/1M | $5.00 | $2.00 |
| Output $/1M | $30.00 | $10.00 |
| Blended $/1M | $11.25 | $4.00 |
| Context window | 1.1M | 1M |
| Max output | 128K | 128K |
| Released | Apr 2026 | Jun 2026 |
| Licence | Proprietary | Proprietary |
| GPQA Diamond | 90.7% | 90.5% |
| FrontierMath T1–3 | 85.3% | 65.6% |
| FrontierMath T4 | 72.5% | 29.3% |
| OTIS Mock AIME | 84.4% | 94.7% |
Benchmark scores independently run and published by Epoch AI, 'AI Benchmarking Hub', used under CC BY 4.0. Only benchmarks with a score for BOTH models are compared.
Choose GPT-5.5 if…
- Higher GPQA Diamond (90.7% vs 90.5%)
- Higher FrontierMath T1–3 (85.3% vs 65.6%)
- Higher FrontierMath T4 (72.5% vs 29.3%)
- Larger context window (1.1M)
Choose Claude Sonnet 5 if…
- Costs less per token — $4.00 vs $11.25 blended
- Higher OTIS Mock AIME (94.7% vs 84.4%)
- Newer model (released Jun 2026)
FAQ
Which is better, GPT-5.5 or Claude Sonnet 5?
Across the 4 benchmarks both models have independently-run scores for, GPT-5.5 leads on 3 and Claude Sonnet 5 leads on 1. Benchmarks are one input — price and context window are on this page too.
Is GPT-5.5 cheaper than Claude Sonnet 5?
Claude Sonnet 5 is cheaper: $4.00 versus $11.25 per million tokens blended at 3:1 input:output. Input alone: $5.00 vs $2.00. Output alone: $30.00 vs $10.00.
What context windows do GPT-5.5 and Claude Sonnet 5 have?
GPT-5.5: 1,050,000 tokens. Claude Sonnet 5: 1,000,000 tokens.
Who makes GPT-5.5 and Claude Sonnet 5?
GPT-5.5 is made by OpenAI. Claude Sonnet 5 is made by Anthropic.