Model comparison · updated 2026-07-28
Side-by-side pricing for1 million tokens
| GPT-5.5 | Gemini 3.1 Pro | Verdict | |
|---|---|---|---|
| Provider | OpenAI | -- | |
| Context window | 400K | 1M | -- |
| Input / 1M tokens | $5 | $2 | Gemini 3.1 Pro is 2.5x cheaper |
| Output / 1M tokens | $30 | $12 | Gemini 3.1 Pro is 2.5x cheaper |
| Output:input ratio | 6x | 6x | -- |
| Tier | flagship | balanced | -- |
GPT-5.5: Long-context (>272K input) priced at 2× input / 1.5× output.
Gemini 3.1 Pro: Prices double for prompts above 200K tokens ($4 / $18).
GPT-5.5
2,000,000 tokens
Gemini 3.1 Pro
5,000,000 tokens
Gemini 3.1 Pro gives you 2.5x more input for the same budget.
GPT-5.5
333,333 tokens
Gemini 3.1 Pro
833,333 tokens
Gemini 3.1 Pro gives you 2.5x more output for the same budget.