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Google · Image API

Nano Banana Pro

nano-banana-pro-ext

Gemini 3 Pro Image route for professional generation, reference editing, and native 4K output.

POST/v1/images/generations
Output count1–1
Reference imagesUp to 14
Resolution tiers1K · 2K · 4K
Generation

Generate with Nano Banana Pro

Use ImgRouter's unified request contract and this model ID. The example uses recommended defaults from the route's current parameter guide.

cURL
curl https://api.imgrouter.com/v1/images/generations \
  -H "Authorization: Bearer $IMGROUTER_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: nano-banana-pro-ext-generate-001" \
  -d '{
  "model": "nano-banana-pro-ext",
  "prompt": "Editorial product photograph, precise materials, soft studio light",
  "size": "16:9",
  "resolution": "2K",
  "n": 1
}'

Request body

modelstring · requiredUse nano-banana-pro-ext.
promptstring · requiredGeneration or editing instruction between 1 and 5,000 characters.
sizestringSupported values: auto, 1:1, 2:3, 3:2, 3:4, 4:3, 4:5, 5:4, 9:16, 16:9, 21:9.
resolutionstringSupported values: 1K, 2K, 4K.
ninteger · 1–1Number of output images. Defaults to 1 and cannot exceed 1.
reference_imagesstring[] · max 14Public HTTPS source images. Send this field to the edit endpoint.
Controls

Supported options

Aspect ratio or size

auto1:12:33:23:44:34:55:49:1616:921:9

Resolution

1K2K4K

Output format

url

Route notes

Professional generation and editing route with up to fourteen references.

One image is generated per request.

4K requests take longer; use 1K or 2K during iteration.

Reference workflow

Edit with reference images

Send public HTTPS source images with the same core controls. This route accepts up to 14 reference images.

POST/v1/images/edits
cURL
curl https://api.imgrouter.com/v1/images/edits \
  -H "Authorization: Bearer $IMGROUTER_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: nano-banana-pro-ext-edit-001" \
  -d '{
  "model": "nano-banana-pro-ext",
  "prompt": "Preserve the subject and composition. Change the scene to soft blue hour.",
  "size": "16:9",
  "resolution": "2K",
  "n": 1,
  "reference_images": [
    "https://example.com/reference.jpg"
  ]
}'

Describe both the intended change and the details that must remain consistent. Stable source URLs produce the most reliable edit requests.

Response

Read the completed output

Successful requests return completed image URLs and a request ID. Store the assets you need permanently; routed output URLs may expire.

200 · application/json
{
  "id": "req_01K4…",
  "object": "image.generation",
  "created": 1787424152,
  "data": [
    { "url": "https://static.imgrouter.com/images/req_01K4.webp" }
  ],
  "usage": { "images": 1 }
}

Use GET /v1/requests/{request_id} for reconciliation and GET /v1/balance for the authenticated key's current Credit position.