Google · Released 2026-02-28

Nano Banana 2 (Gemini 3.1 Flash Image Preview)

Name: Nano Banana 2 (Gemini 3.1 Flash Image Preview)
Brand: Google
Price: 0.50 USD
Availability: InStock

Text → ImageImage → Image

Gemini 3.1 Flash Image Preview (“Nano Banana 2”) is Google’s next-generation image generation and editing model, combining Pro-level visual quality with Flash-level speed and cost efficiency. It delivers stronger contextual understanding, high-fidelity image creation, and fast iterative editing for a wide range of creative and production workflows. Developers can customize output composition and aspect ratios through the image_config API parameter.

google/gemini-3.1-flash-image-preview

Official example

Input

Prompt

将画面中的男性替换为女性，该女性手持香蕉

Output

Parameters

Derived from the model input schema

Parameter	Type	Default	Description
`prompt`Required	string	—	提示词
`aspect_ratio`	string	1:1	宽高比1:1 · 1:4 · 1:8 · 3:2 · 2:3 · 3:4 …
`response_modalities`	array	IMAGE	响应模态
`size`	string	1K	图像大小0.5K · 1K · 2K · 4K
`image`Required	string	—	图片Url
`images`Required	array	—	图片Url数组1 – 10

API example

Submit a generation task, then poll for the result — one API key for every model.

Get API Key Get API Key

# Submit task
curl https://router-integration.test.cogfoundry.ai/api/v1/tasks/generations \
  -H "Authorization: Bearer $MODEL_CENTER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "google/gemini-3.1-flash-image-preview",
  "aspect_ratio": "16:9",
  "image": "https://oss.shengsuanyun.com/example/modelinfo/283/input_0.jpg",
  "prompt": "将画面中的男性替换为女性，该女性手持香蕉",
  "response_modalities": [
    "IMAGE"
  ],
  "size": "1K"
}'

# Poll result（REQUEST_ID 来自上一步返回的 data.request_id）
curl https://router-integration.test.cogfoundry.ai/api/v1/tasks/generations/REQUEST_ID \
  -H "Authorization: Bearer $MODEL_CENTER_API_KEY"

import requests

BASE = "https://router-integration.test.cogfoundry.ai/api/v1"
KEY = "$MODEL_CENTER_API_KEY"
headers = {"Authorization": f"Bearer {KEY}", "Content-Type": "application/json"}

# Submit task
resp = requests.post(f"{BASE}/tasks/generations", headers=headers, data='''{
  "model": "google/gemini-3.1-flash-image-preview",
  "aspect_ratio": "16:9",
  "image": "https://oss.shengsuanyun.com/example/modelinfo/283/input_0.jpg",
  "prompt": "将画面中的男性替换为女性，该女性手持香蕉",
  "response_modalities": [
    "IMAGE"
  ],
  "size": "1K"
}''')
request_id = resp.json()["data"]["request_id"]

# Poll result
result = requests.get(f"{BASE}/tasks/generations/{request_id}", headers=headers)
print(result.json())

const BASE = "https://router-integration.test.cogfoundry.ai/api/v1";
const KEY = "$MODEL_CENTER_API_KEY";
const headers = { Authorization: "Bearer " + KEY, "Content-Type": "application/json" };

// Submit task
const payload = {
  "model": "google/gemini-3.1-flash-image-preview",
  "aspect_ratio": "16:9",
  "image": "https://oss.shengsuanyun.com/example/modelinfo/283/input_0.jpg",
  "prompt": "将画面中的男性替换为女性，该女性手持香蕉",
  "response_modalities": [
    "IMAGE"
  ],
  "size": "1K"
};
const resp = await fetch(BASE + "/tasks/generations", {
  method: "POST",
  headers,
  body: JSON.stringify(payload),
});
const { data } = await resp.json();

// Poll result
const result = await fetch(BASE + "/tasks/generations/" + data.request_id, { headers });
console.log(await result.json());