Claude Opus 5.5
Anthropic · released Sep 22, 2026
| size | large, not disclosed by the manufacturer |
| context window | 1,000,000 tokens |
| longest response | 128,000 tokens |
| knowledge cutoff | June 2026 |
| open weights | no |
| API price | $4 per million input tokens, $20 per million output tokens |
| input and output | text and images in, text out |
Manufacturer data (announcement, documentation, pricing), verified Sep 25, 2026.
Where we tested it
Dragon
TaskThe model's task was to draw a picture of a dragon as an SVG.
35 points out of 50, a shared 7th place among 34 dragons. After its first picture it found the anatomy flaws on its own and fixed them.
You'll find the size band and figures for other models on the Tested models page.