OpenAI: GPT-5.5 wins on more metrics (4 of 7), but the right pick depends on what you optimize for — see the breakdown below.
| Metric | OpenAI: GPT-3.5 Turbo 16k | OpenAI: GPT-5.5 |
|---|---|---|
| Intelligence Index | — | — |
| Coding Index | — | — |
| GPQA Diamond | — | 93%✓ |
| Design Arena Elo | — | 1348✓ |
| Speed (tokens/sec) | 14 | 39✓ |
| Latency | 654ms✓ | 3.0s |
| Input price /M | $3.00✓ | $5.00 |
| Output price /M | $4.00✓ | $30.00 |
| Context window | 16K | 1.1M✓ |
| Capabilities | ToolsJSON | ReasoningToolsJSONVision |