Gemini Nano parameters and API differences

Match Nano Banana names to platform model IDs and compare image sizes, aspect ratios and reference image rules.

See Create / edit images for requests and examples. Use the platform model ID in the path.

Applicable models

Common aspect ratios are 1:1, 2:3, 3:2, 3:4, 4:3, 4:5, 5:4, 9:16, 16:9 and 21:9.

Model	Sizes and aspect ratios	Reference images
Nano Banana 2.1	`1K`, `2K`, `4K`, plus `1:4`, `4:1`, `1:8`, `8:1`.	Google Cloud specifies up to 14 images per request.
Nano Banana Pro	`1K`, `2K`, `4K` and common aspect ratios.	Up to 14 in total. Google's image guide separately lists high-fidelity references of up to 6 objects and 5 people.
Nano Banana 2	`512`, `1K`, `2K`, `4K`, plus `1:4`, `4:1`, `1:8`, `8:1`.	Up to 14 in total. Up to 10 high-fidelity object references, with consistency for up to 4 characters.
Nano Banana	Common aspect ratios. Dimensions vary by ratio, with square images at 1024 × 1024.	Google recommends 1–3 images for best results.

Model	Usage notes
Nano Banana 2.1	Supports thinking and multi-turn editing. Google's model documentation lists video input, web search and image search.
Nano Banana Pro	Supports thinking, web search and multi-turn editing.
Nano Banana 2	Supports thinking, video input, web search, image search and multi-turn editing.
Nano Banana	Supports reference-based editing. Use the previous output as a reference for the next request.

When replaying editing history, preserve the returned content and its thoughtSignature unchanged.