Claude Sonnet 5.5 vs GPT-6.1 Sol
Claude Sonnet 5.5 is from Anthropic. GPT-6.1 Sol is from OpenAI. Claude Sonnet 5.5 costs $10.00 per million output tokens. GPT-6.1 Sol costs $10.00. GPT-6.1 Sol leads on the Epoch Capabilities Index: Claude Sonnet 5.5 scores 166.7 and GPT-6.1 Sol scores 167.8. A typical request, about 1,000 words in and 400 words out, costs $0.0076 on Claude Sonnet 5.5 and $0.0076 on GPT-6.1 Sol.
Prices updated . Benchmarks updated .
| Claude Sonnet 5.5 | GPT-6.1 Sol | |
|---|---|---|
| Lab | Anthropic | OpenAI |
| You send / 1M | $2.00 | $2.00 |
| It replies / 1M | $10.00 | $10.00 |
| Context | 1M | 1.05M |
| Launched | 2026-09-28 | 2026-09-29 |
| Weights | Closed | Closed |
| Typical request | $0.0076 | $0.0076 |
| ECI | 166.7 | 167.8 |
| GPQA | 95.6% | 95.4% |
| ARC-AGI-2 | 83.9% | 94.2% |
| HLE | 46.1% | n/a |
| AIME | 100.0% | 100.0% |
| SimpleQA | 46.5% | 73.9% |
| CritPt | 31.4% | 31.7% |
| Arena | 1,473 | 1,446 |
| Arena web | 1,770 | 1,751 |
Which is cheaper?
Claude Sonnet 5.5 and GPT-6.1 Sol cost the same for output tokens, $10.00 per million. Input tokens are $2.00 per million for Claude Sonnet 5.5 and $2.00 per million for GPT-6.1 Sol. A typical request, about 1,000 words in and 400 words out, costs $0.0076 on Claude Sonnet 5.5 and $0.0076 on GPT-6.1 Sol.
Which scores higher?
GPT-6.1 Sol scores higher on Epoch Capabilities Index: 167.8 against 166.7 for Claude Sonnet 5.5. That index is an independent composite from Epoch AI. Lab-reported scores are kept off this comparison. Context windows are 1M and 1.05M. Prices are US dollars per million tokens at current public rates.
Verdict
GPT-6.1 Sol scores higher on Epoch Capabilities Index (167.8 vs 166.7). A public token price is missing for at least one model, so this page does not call a cheaper winner. Context is 1M for Claude Sonnet 5.5 and 1.05M for GPT-6.1 Sol. Use the model pages for every score on file, including lab-reported numbers.
FAQ
Which is cheaper, Claude Sonnet 5.5 vs GPT-6.1 Sol?
Claude Sonnet 5.5 and GPT-6.1 Sol cost the same for output tokens, $10.00 per million. Input tokens are $2.00 per million for Claude Sonnet 5.5 and $2.00 per million for GPT-6.1 Sol. A typical request, about 1,000 words in and 400 words out, costs $0.0076 on Claude Sonnet 5.5 and $0.0076 on GPT-6.1 Sol.
Which scores higher, Claude Sonnet 5.5 vs GPT-6.1 Sol?
GPT-6.1 Sol scores higher on Epoch Capabilities Index: 167.8 against 166.7 for Claude Sonnet 5.5. That index is an independent composite from Epoch AI. Lab-reported scores are kept off this comparison. Context windows are 1M and 1.05M. Prices are US dollars per million tokens at current public rates.
What is the verdict for Claude Sonnet 5.5 vs GPT-6.1 Sol?
GPT-6.1 Sol scores higher on Epoch Capabilities Index (167.8 vs 166.7). A public token price is missing for at least one model, so this page does not call a cheaper winner. Context is 1M for Claude Sonnet 5.5 and 1.05M for GPT-6.1 Sol. Use the model pages for every score on file, including lab-reported numbers.
Open this pair in the comparison view
Sources and licenses
- OpenRouter: Prices, context windows, modalities and the model list come from the OpenRouter public API. Data: OpenRouter.
- Vercel AI Gateway: The no-training flag comes from the Vercel AI Gateway model list.
- models.dev: Lab launch dates, open-weights flags and knowledge cutoffs come from models.dev. Copyright (c) 2025 models.dev, MIT License.
- Epoch AI: Independent benchmark scores and the Epoch Capabilities Index (ECI) come from Epoch AI's Benchmarking Hub, used under CC BY 4.0. Epoch AI, Capabilities & benchmarking, epoch.ai/benchmarks. Scores Epoch marks as external keep their original license, and the source is named on each score.
- LMArena: Arena Elo (text, webdev and vision) comes from the LMArena leaderboard dataset (lmarena-ai/leaderboard-dataset), CC BY 4.0, leaderboard date 2026-10-28.
- Lab-reported scores, when an editor has added them, are the lab's own numbers. Each one links to the source and is labeled lab-reported. They are not used to rank the lists.
- What a score measures: the benchmark guide.