Nano Banana Fast Image API Parameters

The Nano Banana Fast asynchronous image contract accepted by this API.

Provider: Volcano Engine China · Last verified: 2026-08-17

Model summary

Provider: GRSAI
Region: Global
Fixed credit cost: 20
Output type: image
Operations: generation, edit
Image sizes: 1K

Generation request

json

{
  "model": "nano-banana-fast",
  "prompt": "A cinematic product photograph with soft studio lighting",
  "aspect_ratio": "1:1",
  "image_size": "1K",
  "response_format": "url"
}

Image field contract

Field	Use	Values
`model`	Required model ID	nano-banana-fast
`prompt`	Required generation or editing instruction	1–20,000 characters
`aspect_ratio`	Output ratio	auto, 1:1, 16:9, 9:16, 4:3, 3:4
`image_size`	Resolution tier	1K
`image_urls`	Required only for edits	1–16 public HTTPS URLs
`response_format`	Optional	url

Review the image API guide.