Google Gemini 2.5 Flash vs OpenAI GPT-5-Codex — side-by-side specs.
Google Gemini 2.5 Flash | OpenAI GPT-5-Codex | |
|---|---|---|
| Overview | ||
| Company | OpenAI | |
| Release date | Apr 17 2025 | Sep 15 2025 |
| Model type | — | — |
| Open source | No | No |
| Specifications | ||
Parameters | — | — |
Context window | — | — |
| Benchmarks | ||
| Timeline | ||
| Release gap | Gemini 2.5 Flash shipped 151 days before GPT-5-Codex | |
Gemini 2.5 Flash and GPT-5-Codex don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Gemini 2.5 Flash shipped 151 days before GPT-5-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 — Gemini 2.5 Flash and GPT-5-Codex don't publish scores on any of the same benchmarks.