Gemini 3.5 Flash vs GPT-5 Codex
Google vs OpenAI — benchmarks, pricing, and capabilities side by side.
- •Gemini 3.5 Flash has the higher intelligence index (92.2 vs 87.1)
- •GPT-5 Codex is cheaper ($1.25 vs $1.50 per 1M input)
- •Gemini 3.5 Flash is faster
- •Gemini 3.5 Flash has a larger context window (1M)
| Gemini 3.5 Flash | GPT-5 Codex | |
|---|---|---|
| Intelligence index | 92.2 | 87.1 |
| Developer | OpenAI | |
| Type | Multimodal | Multimodal |
| Access | API only | API only |
| Context window | 1,048,576 tokens | 400,000 tokens |
| Input price | $1.50 / 1M | $1.25 / 1M |
| Output price | $9.00 / 1M | $10.00 / 1M |
| Speed | 221 tok/s | 180 tok/s |
| Released | May 19, 2026 | September 23, 2025 |
| Parameters | — | — |
| Input modalities | Text, Image, Audio, Video | Text, Image |
| Output modalities | Text | Text |
Shared benchmarks
Gemini 3.5 Flash
GPT-5 Codex
GPQA Diamond
92.2
83.7
Humanity’s Last Exam
41
25.6