Nano Banana 2.1 API reference

Name: Nano Banana 2.1 API
Brand: Google
Availability: InStock

Everything you need to call Nano Banana 2.1 from your code. Base URL https://cheapergen.com/api/v1. Try it first in the playground.

Authentication

Create a key in Dashboard → API keys and send it as a bearer token. Keep keys server-side.

export CHEAPERGEN_API_KEY="cg_live_…"

# every request
Authorization: Bearer $CHEAPERGEN_API_KEY

Nano Banana 2.1 Text to Image API

POST/api/v1/run/google/nano-banana-2.1/text-to-image

Submits an asynchronous job and returns 202 with a generation id. Poll GET /api/v1/generations/{id} or pass webhook_url. See job lifecycle.

Input parameters

Name	Type	Description	Affects price
`prompt`required	string	Describe the shot: subject, action, camera movement, lighting and style.	No
`aspect_ratio`	string (enum)	Output image shape. Values: 1:1 · 2:3 · 3:2 · 3:4 · 4:3 · 4:5 · 5:4 · 9:16 · 16:9 · 21:9 · 1:4 · 4:1 · 1:8 · 8:1 Default: 1:1	Yes
`resolution`	string (enum)	Output size: 1K ≈ 1 megapixel, 2K ≈ 4 MP, 4K ≈ 16 MP. Values: 1K · 2K · 4K Default: 1K	Yes
`webhook_url`	string (URL)	Optional. We POST the finished generation here, signed with your webhook secret. Webhooks	No

Request

curl -X POST https://cheapergen.com/api/v1/run/google/nano-banana-2.1/text-to-image \
  -H "Authorization: Bearer $CHEAPERGEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "prompt": "A cozy ramen shop at night in the rain, warm light spilling onto wet pavement, a neon sign that reads “OPEN”, photorealistic",
  "aspect_ratio": "1:1",
  "resolution": "1K"
}'

import os, time, requests

API = "https://cheapergen.com/api/v1"
headers = {"Authorization": f"Bearer {os.environ['CHEAPERGEN_API_KEY']}"}

# 1. Submit the job
job = requests.post(f"{API}/run/google/nano-banana-2.1/text-to-image", headers=headers, json={
    "prompt": "A cozy ramen shop at night in the rain, warm light spilling onto wet pavement, a neon sign that reads “OPEN”, photorealistic",
    "aspect_ratio": "1:1",
    "resolution": "1K"
}).json()

# 2. Poll until it finishes (or pass "webhook_url" and skip polling)
while job["status"] in ("queued", "running"):
    time.sleep(3)
    job = requests.get(f"{API}/generations/{job['id']}", headers=headers).json()

print(job["status"], job["output"]["images"][0]["url"] if job["status"] == "succeeded" else job["error"])

const API = "https://cheapergen.com/api/v1";
const headers = {
  Authorization: `Bearer ${process.env.CHEAPERGEN_API_KEY}`,
  "Content-Type": "application/json",
};

// 1. Submit the job
let job = await fetch(`${API}/run/google/nano-banana-2.1/text-to-image`, {
  method: "POST",
  headers,
  body: JSON.stringify({
    "prompt": "A cozy ramen shop at night in the rain, warm light spilling onto wet pavement, a neon sign that reads “OPEN”, photorealistic",
    "aspect_ratio": "1:1",
    "resolution": "1K"
  }),
}).then((r) => r.json());

// 2. Poll until it finishes (or pass webhook_url and skip polling)
while (job.status === "queued" || job.status === "running") {
  await new Promise((r) => setTimeout(r, 3000));
  job = await fetch(`${API}/generations/${job.id}`, { headers }).then((r) => r.json());
}

console.log(job.status === "succeeded" ? job.output.images[0].url : job.error);

Response

{
  "id": "gen_8c2QmX1nq0k4",
  "object": "generation",
  "model": "google/nano-banana-2.1",
  "endpoint": "google/nano-banana-2.1/text-to-image",
  "mode": "text-to-image",
  "status": "queued",
  "input": {
    "prompt": "A cozy ramen shop at night in the rain, warm light spilling onto wet pavement, a neon sign that reads “OPEN”, photorealistic",
    "aspect_ratio": "1:1",
    "resolution": "1K"
  },
  "output": null,
  "error": null,
  "cost": {
    "amount_usd": 0.2255,
    "currency": "usd",
    "estimated": true,
    "official_usd": null,
    "saved_usd": null
  },
  "source": "api",
  "started_at": null,
  "completed_at": null,
  "urls": {
    "get": "https://cheapergen.com/api/v1/generations/gen_8c2QmX1nq0k4",
    "cancel": "https://cheapergen.com/api/v1/generations/gen_8c2QmX1nq0k4/cancel"
  },
  "created_at": "2026-10-15T09:21:04Z"
}

{
  "id": "gen_8c2QmX1nq0k4",
  "object": "generation",
  "model": "google/nano-banana-2.1",
  "endpoint": "google/nano-banana-2.1/text-to-image",
  "mode": "text-to-image",
  "status": "succeeded",
  "input": {
    "prompt": "A cozy ramen shop at night in the rain, warm light spilling onto wet pavement, a neon sign that reads “OPEN”, photorealistic",
    "aspect_ratio": "1:1",
    "resolution": "1K"
  },
  "output": {
    "images": [
      {
        "url": "https://cdn.cheapergen.ai/outputs/gen_8c2Q-0.png",
        "content_type": "image/png",
        "width": 2048,
        "height": 2048
      }
    ]
  },
  "error": null,
  "cost": {
    "amount_usd": 0.2255,
    "currency": "usd",
    "estimated": false,
    "official_usd": 0.264,
    "saved_usd": 0.0385
  },
  "source": "api",
  "created_at": "2026-10-15T09:21:04Z",
  "started_at": "2026-10-15T09:21:06Z",
  "completed_at": "2026-10-15T09:22:31Z"
}

Nano Banana 2.1 Image Edit API

POST/api/v1/run/google/nano-banana-2.1/edit

Submits an asynchronous job and returns 202 with a generation id. Poll GET /api/v1/generations/{id} or pass webhook_url. See job lifecycle.

Input parameters

Name	Type	Description	Affects price
`prompt`required	string	Describe the shot: subject, action, camera movement, lighting and style.	No
`image_urls`required	string[] (URLs)	Up to 14 images to edit or combine — products, people, styles. Refer to them as "image 1", "image 2"… in the prompt. Max items: 14	No
`aspect_ratio`	string (enum)	Output image shape. Values: 1:1 · 2:3 · 3:2 · 3:4 · 4:3 · 4:5 · 5:4 · 9:16 · 16:9 · 21:9 · 1:4 · 4:1 · 1:8 · 8:1 Default: 1:1	Yes
`resolution`	string (enum)	Output size: 1K ≈ 1 megapixel, 2K ≈ 4 MP, 4K ≈ 16 MP. Values: 1K · 2K · 4K Default: 1K	Yes
`webhook_url`	string (URL)	Optional. We POST the finished generation here, signed with your webhook secret. Webhooks	No

Request

curl -X POST https://cheapergen.com/api/v1/run/google/nano-banana-2.1/edit \
  -H "Authorization: Bearer $CHEAPERGEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "prompt": "Put the product from image 1 on the marble counter in image 2, matching the soft morning light",
  "image_urls": [
    "https://cdn.cheapergen.ai/samples/portrait.jpg"
  ],
  "aspect_ratio": "1:1",
  "resolution": "1K"
}'

import os, time, requests

API = "https://cheapergen.com/api/v1"
headers = {"Authorization": f"Bearer {os.environ['CHEAPERGEN_API_KEY']}"}

# 1. Submit the job
job = requests.post(f"{API}/run/google/nano-banana-2.1/edit", headers=headers, json={
    "prompt": "Put the product from image 1 on the marble counter in image 2, matching the soft morning light",
    "image_urls": [
        "https://cdn.cheapergen.ai/samples/portrait.jpg"
    ],
    "aspect_ratio": "1:1",
    "resolution": "1K"
}).json()

# 2. Poll until it finishes (or pass "webhook_url" and skip polling)
while job["status"] in ("queued", "running"):
    time.sleep(3)
    job = requests.get(f"{API}/generations/{job['id']}", headers=headers).json()

print(job["status"], job["output"]["images"][0]["url"] if job["status"] == "succeeded" else job["error"])

const API = "https://cheapergen.com/api/v1";
const headers = {
  Authorization: `Bearer ${process.env.CHEAPERGEN_API_KEY}`,
  "Content-Type": "application/json",
};

// 1. Submit the job
let job = await fetch(`${API}/run/google/nano-banana-2.1/edit`, {
  method: "POST",
  headers,
  body: JSON.stringify({
    "prompt": "Put the product from image 1 on the marble counter in image 2, matching the soft morning light",
    "image_urls": [
      "https://cdn.cheapergen.ai/samples/portrait.jpg"
    ],
    "aspect_ratio": "1:1",
    "resolution": "1K"
  }),
}).then((r) => r.json());

// 2. Poll until it finishes (or pass webhook_url and skip polling)
while (job.status === "queued" || job.status === "running") {
  await new Promise((r) => setTimeout(r, 3000));
  job = await fetch(`${API}/generations/${job.id}`, { headers }).then((r) => r.json());
}

console.log(job.status === "succeeded" ? job.output.images[0].url : job.error);

Response

{
  "id": "gen_8c2QmX1nq0k4",
  "object": "generation",
  "model": "google/nano-banana-2.1",
  "endpoint": "google/nano-banana-2.1/edit",
  "mode": "edit",
  "status": "queued",
  "input": {
    "prompt": "Put the product from image 1 on the marble counter in image 2, matching the soft morning light",
    "image_urls": [
      "https://cdn.cheapergen.ai/samples/portrait.jpg"
    ],
    "aspect_ratio": "1:1",
    "resolution": "1K"
  },
  "output": null,
  "error": null,
  "cost": {
    "amount_usd": 0.2255,
    "currency": "usd",
    "estimated": true,
    "official_usd": null,
    "saved_usd": null
  },
  "source": "api",
  "started_at": null,
  "completed_at": null,
  "urls": {
    "get": "https://cheapergen.com/api/v1/generations/gen_8c2QmX1nq0k4",
    "cancel": "https://cheapergen.com/api/v1/generations/gen_8c2QmX1nq0k4/cancel"
  },
  "created_at": "2026-10-15T09:21:04Z"
}

{
  "id": "gen_8c2QmX1nq0k4",
  "object": "generation",
  "model": "google/nano-banana-2.1",
  "endpoint": "google/nano-banana-2.1/edit",
  "mode": "edit",
  "status": "succeeded",
  "input": {
    "prompt": "Put the product from image 1 on the marble counter in image 2, matching the soft morning light",
    "image_urls": [
      "https://cdn.cheapergen.ai/samples/portrait.jpg"
    ],
    "aspect_ratio": "1:1",
    "resolution": "1K"
  },
  "output": {
    "images": [
      {
        "url": "https://cdn.cheapergen.ai/outputs/gen_8c2Q-0.png",
        "content_type": "image/png",
        "width": 2048,
        "height": 2048
      }
    ]
  },
  "error": null,
  "cost": {
    "amount_usd": 0.2255,
    "currency": "usd",
    "estimated": false,
    "official_usd": 0.264,
    "saved_usd": 0.0385
  },
  "source": "api",
  "created_at": "2026-10-15T09:21:04Z",
  "started_at": "2026-10-15T09:21:06Z",
  "completed_at": "2026-10-15T09:22:31Z"
}

Get the result

Generations are asynchronous. Poll until status is succeeded, failed or canceled — or pass webhook_url when you submit. Failed generations are refunded automatically.

curl https://cheapergen.com/api/v1/generations/gen_8c2QmX1nq0k4 \
  -H "Authorization: Bearer $CHEAPERGEN_API_KEY"

More: job lifecycle · webhooks · errors

Nano Banana 2.1 pricing

Pay per image. No subscription. Failed generations are refunded automatically.

Tier	Official price	Cheaper Gen.	You save
1K ≈1 MP	~~$0.042~~/img	$0.037/img	−12%
2K ≈4 MP	~~$0.058~~/img	$0.051/img	−12%
4K ≈16 MP	~~$0.121~~/img	$0.107/img	−12%

Official price: Gemini API list price for gemini-nano-banana-2.1 ($30 / 1M image output tokens: $0.0336 at 1K, $0.0504 at 2K, $0.1134 at 4K; input $1.50 / 1M, thinking $7.50 / 1M tokens). Prices verified 2026-10-16.
Prices include the prompt and the model's reasoning tokens; each input image adds about $0.002.