OpenAI: GPT-5.5 Pro wins on more metrics (3 of 5), but the right pick depends on what you optimize for — see the breakdown below.
| Metric | OpenAI: GPT-5 Pro | OpenAI: GPT-5.5 Pro |
|---|---|---|
| Intelligence Index | — | — |
| Coding Index | — | — |
| GPQA Diamond | — | — |
| Design Arena Elo | — | — |
| Speed (tokens/sec) | — | 17✓ |
| Latency | — | 50.2s✓ |
| Input price /M | $15.00✓ | $30.00 |
| Output price /M | $120.00✓ | $180.00 |
| Context window | 400K | 1.1M✓ |
| Capabilities | ReasoningToolsJSONVision | ReasoningToolsJSONVision |