GPT-6 Astra Pro
OpenAI · released Sep 3, 2026
| size | huge, not disclosed by the manufacturer |
| context window | 1,050,000 tokens |
| longest response | 128,000 tokens |
| knowledge cutoff | April 2026 |
| open weights | no |
| API price | $10 per million input tokens, $50 per million output tokens |
| input and output | text and images in, text out |
Manufacturer data (model page, announcement, pricing), verified Sep 25, 2026.
Where we tested it
The silence test
TaskThe model had to stay quiet for a moment; the correct reply had zero characters.
It stayed silent in all six tries, in Czech and in English.
You'll find the size band and figures for other models on the Tested models page.