Nano Banana
Fast text-to-image and reference-image editing. Every accepted parameter, default and price in one place.
/api/v1/generations6 credits per image at every quality setting. Reference images do not add an extra charge. Check credits_refunded to confirm a refund; unresolved submissions may require review.
Authorization
AuthorizationstringrequiredBearer fx1_live_… — send your API key in the request header. API access requires administrator approval.
Idempotency-KeystringoptionalUse one unique value per generation and reuse it with the same body on retries. Printable ASCII, no spaces. A different body with the same key returns 409.
Maximum length: 128 characters
Request body
modelstringrequiredUse this exact model ID in the top-level request body.
nano-bananapromptstringrequiredDescribe the image to create, or the changes to make to your reference images. Whitespace is trimmed.
Maximum length: 5,000 characters
imagesstring[]optionalOptional reference images. Use publicly accessible HTTPS URLs or data:image/* base64 URIs (up to 20,000,000 characters per entry). Omit for text-to-image.
Maximum items: 14
aspect_ratiostringoptionalOutput width-to-height ratio. Auto lets the model choose.
Default: 1:1
auto1:12:33:23:44:34:55:49:1616:921:9resolutionstringoptionalOutput resolution tier; values are case-insensitive. Omit or leave empty to use the default.
Default: 1K
1KResponse & next step
A successful submission returns 202 and a generation id. Poll GET /api/v1/generations/{id} every 2–3 seconds until the status is succeeded or failed.
Read the image URL from output.images[0].url. On failure, inspect error and credits_refunded. Returned dimensions are optional.