Nano Banana Fast Image API Guide

About the Nano Banana Fast API

Nano Banana Fast is the 1K route for compact generation and editing tasks with a low fixed local credit cost.

Available image sizes: 1K
Operations: generation and edit
Fixed local cost: 20 credits per task
Result delivery: asynchronous task polling

Best uses for Nano Banana Fast

Fast 1K creative iterationReview the request contract below before choosing this model for production traffic.

Lower-credit image generationReview the request contract below before choosing this model for production traffic.

1K edits that do not require larger output tiersReview the request contract below before choosing this model for production traffic.

Model summary

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

Compare related models

Compare Nano Banana Fast with nearby model routes before locking an output size, duration or credit budget into your integration.

Nano Banana ProNano Banana Pro is a multi-resolution image generation and editing route with 1K, 2K and 4K output options.Nano Banana Pro VTNano Banana Pro VT exposes the VT model route for asynchronous generation and editing in 1K, 2K or 4K.Nano Banana 2Nano Banana 2 is a multi-resolution generation and editing route covering 1K, 2K and 4K at a fixed local task cost.

Nano Banana Fast API FAQ

What can Nano Banana Fast do?

Nano Banana Fast supports asynchronous generation and edit. Nano Banana Fast is the 1K route for compact generation and editing tasks with a low fixed local credit cost.

Which output sizes does Nano Banana Fast support?

Nano Banana Fast supports 1K. Use the exact model ID and size fields documented on this page so the request can be validated locally.

How many credits does Nano Banana Fast use?

The current local price is 20 credits per generation or editing task. The task stores its quoted cost when it is created.