Claude Opus 5.5 vs GPT-5.1-Codex
| Claude Opus 5.5 | GPT-5.1-Codex | |
|---|---|---|
| Coding index | 88.8 | 15.3 |
| Benchmarks behind it | Verified, 5 benchmarks | Partial, 2 benchmarks |
| Output $/Mtok | $20.00 | $10.00 |
| Cost per solved task | Not computable | $0.892 |
| Context window | 1M | 400K |
| Claude Opus 5.5 | GPT-5.1-Codex | |
|---|---|---|
| Coding index | 88.8 | 15.3 |
| Benchmarks behind it | Verified, 5 benchmarks | Partial, 2 benchmarks |
| Output $/Mtok | $20.00 | $10.00 |
| Cost per solved task | Not computable | $0.892 |
| Context window | 1M | 400K |