GPT-5.5 vs Claude Sonnet 4.5 (latest)
30-second takeaway
- Claude Sonnet 4.5 (latest) has the cheaper input: $3 vs $5 (per 1M tokens, 40% less)
- GPT-5.5 has the larger context: 1.05M vs 200K tokens
| GPT-5.5 OpenAI | Claude Sonnet 4.5 (latest) Anthropic | |
|---|---|---|
| Input | $5 | $3 |
| Output | $30 | $15 |
| Context | 1.05M | 200K |
More specs (max output / capabilities)
| max output | 128,000 | 64,000 |
| Reasoning | ✓ Yes | ✓ Yes |
| Tool calls | ✓ Yes | ✓ Yes |
| Open weights | — No | — No |
Prices are official/data-source rates (per 1M tokens), not what relays actually charge — relay prices vary with discounts and group multipliers. See methodology.