GPT-5.1 Chat vs Claude Sonnet 4.5
GPT-5.1 Chat is cheaper on output tokens, while Claude Sonnet 4.5 offers a larger context window. Choose GPT-5.1 Chat or Claude Sonnet 4.5 based on the trade-off between cost, context, and the benchmarks that matter for your use case.
| Spec | GPT-5.1 Chat | Claude Sonnet 4.5 |
|---|---|---|
| Provider | Merge Gateway | Merge Gateway |
| Input / 1M tokens | $1.25 | $3.00 |
| Output / 1M tokens | $10.00 | $15.00 |
| Context window | 128K | 200K |
| Parameters | — | — |
| Open weights | No | No |
| Released | Nov 2025 | Sep 2025 |
FAQ
Pricing is indicative — confirm with the provider before production use. Highlighted values indicate the better figure for that row.