Model comparison · updated 2026-07-28
Side-by-side pricing for1 million tokens
| GPT-5.5 | Claude Sonnet 5 | Verdict | |
|---|---|---|---|
| Provider | OpenAI | Anthropic | -- |
| Context window | 400K | 1M | -- |
| Input / 1M tokens | $5 | $2 | Claude Sonnet 5 is 2.5x cheaper |
| Output / 1M tokens | $30 | $10 | Claude Sonnet 5 is 3x cheaper |
| Output:input ratio | 6x | 5x | -- |
| Tier | flagship | balanced | -- |
GPT-5.5: Long-context (>272K input) priced at 2× input / 1.5× output.
Claude Sonnet 5: Introductory pricing — list price is $3 / $15 from Sep 1, 2026.
GPT-5.5
2,000,000 tokens
Claude Sonnet 5
5,000,000 tokens
Claude Sonnet 5 gives you 2.5x more input for the same budget.
GPT-5.5
333,333 tokens
Claude Sonnet 5
1,000,000 tokens
Claude Sonnet 5 gives you 3x more output for the same budget.