2 vs 0 benchmarks won
Anthropic Claude 3.5 Sonnet | OpenAI GPT-5.3-Codex | |
|---|---|---|
| Overview | ||
| Company | Anthropic | OpenAI |
| Release date | Jun 20 2024 | Feb 5 2026 |
| Model type | — | — |
| Open source | No | No |
| Specifications | ||
Parameters | — | — |
Context window | — | — |
| Benchmarks | ||
Science reasoning GPQA Diamond | 59.4% | — |
Software engineering SWE-Bench Verified | 33.4% | — |
Multimodal understanding MMMU | — | — |
| Timeline | ||
| Release gap | Claude 3.5 Sonnet shipped 595 days before GPT-5.3-Codex | |
Claude 3.5 Sonnet leads GPT-5.3-Codex on 2 of the tracked benchmarks (GPQA Diamond, SWE-Bench Verified, MMMU). Claude 3.5 Sonnet shipped 595 days before GPT-5.3-Codex, so benchmark comparisons should account for the intervening progress.
Published specifications for these two models are limited — see each model page for the latest details.
Direct benchmark comparisons are unavailable — at least one of these models has not published scores on GPQA Diamond, SWE-Bench Verified, or MMMU.