Gemini 3.1 Pro vs GPT-5.3-Codex
Google vs OpenAI — benchmarks, pricing, and capabilities side by side.
- •GPT-5.3-Codex has the higher intelligence index (91.5 vs 83.2)
- •GPT-5.3-Codex is cheaper ($1.75 vs $2.00 per 1M input)
- •Gemini 3.1 Pro is faster
- •Gemini 3.1 Pro has a larger context window (1M)
| Gemini 3.1 Pro | GPT-5.3-Codex | |
|---|---|---|
| Intelligence index | 83.2 | 91.5 |
| Developer | OpenAI | |
| Type | Multimodal | Multimodal |
| Access | API only | API only |
| Context window | 1,048,576 tokens | 400,000 tokens |
| Input price | $2.00 / 1M | $1.75 / 1M |
| Output price | $12.00 / 1M | $14.00 / 1M |
| Speed | 142 tok/s | 73 tok/s |
| Released | February 19, 2026 | February 24, 2026 |
| Parameters | — | — |
| Input modalities | Text, Image, Audio, Video | Text, Image |
| Output modalities | Text | Text |
Shared benchmarks
Gemini 3.1 Pro
GPT-5.3-Codex
GPQA Diamond
94.3
91.5
Humanity’s Last Exam
44.4
39.9