Parameters that matter
The three models take the same request parameters. The ones you will set most often:
- size: WIDTHxHEIGHT on a 16-pixel grid, up to 3840 pixels on a side and 3:1, or auto
- quality: low, medium or high; GPT Image 2.5 also accepts xhigh and max
- background: auto, opaque or transparent (transparent needs PNG or WebP)
- output_format: png, jpeg or webp
- n: up to 10 images per request
- reference images: up to 16, each as the subject to keep or a style to imitate