GPT-6 Astra vs Gemini 3.8 Flash
GPT-6 Astra (OpenAI) and Gemini 3.8 Flash (Google) compared on price, context window, speed and independent benchmarks. GPT-6 Astra scores higher on the Artificial Analysis Intelligence Index (61.2 vs 58.7), while Gemini 3.8 Flash is 13.3× cheaper on a blended basis. Pick GPT-6 Astra for the hardest tasks and Gemini 3.8 Flash when cost dominates.
| GPT-6 Astra | Gemini 3.8 Flash | |
|---|---|---|
| Provider | OpenAI | |
| Input $/1M | $10.0 | $0.75 |
| Output $/1M | $50.0 | $3.75 |
| Blended $/1M (3:1) | $20.0 | $1.50 |
| Cached input $/1M | $1.00 | $0.07 |
| Context window | 1.1M | 1.0M |
| Knowledge cutoff | 2026-04 | — |
| License | proprietary | proprietary |
| Speed (tok/s) | — | 417 |
| Artificial Analysis Intelligence Index | 61.2 | 58.7 |
| GPQA Diamond | 96.1% | 95.3% |
| Humanity's Last Exam | 54.7% | 47.8% |