Nanobanana

Nanobanana 2 Lite Image Generation

Nano Banana 2 Lite (gemini-3.1-flash-lite-image) model supports text-to-image, image-to-image, image editing and other generation modes
Asynchronous processing mode, use the returned task ID to query
Generated image links are valid for 24 hours, please save them promptly

POST

images

generations

Nano Banana 2 Lite Interface

curl --request POST \
  --url https://api.apiko.example/v1/images/generations \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "model": "gemini-3.1-flash-lite-image",
  "prompt": "A cat playing on the grass"
}
'

{
  "created": 1757165031,
  "id": "task-unified-1757165031-uyujaw3d",
  "model": "gemini-3.1-flash-lite-image",
  "object": "image.generation.task",
  "progress": 0,
  "status": "pending",
  "task_info": {
    "can_cancel": true,
    "estimated_time": 45
  },
  "type": "image",
  "usage": {
    "billing_rule": "per_call",
    "credits_reserved": 8.7,
    "user_group": "default"
  }
}

Authorizations

Authorization

stringheaderrequired

##All APIs require Bearer Token authentication##

Get API Key:

Visit API Key Management Page to get your API Key

Add to request header:

Authorization: Bearer YOUR_API_KEY

Body

application/json

model

enum<string>default:gemini-3.1-flash-lite-imagerequired

Image generation model name, official channel, better stability and controllability, suitable for commercial scenarios

Available options: gemini-3.1-flash-lite-image

Example:"gemini-3.1-flash-lite-image"

prompt

stringrequired

Prompt describing the image to be generated, or describing how to edit the input image, limited to 2000 tokens

Maximum string length: 2000

Example:"A cat playing in the grass"

size

enum<string>

Aspect ratio of the generated image, default is auto

Available options: auto, 1:1, 1:4, 4:1, 1:8, 8:1, 2:3, 3:2, 3:4, 4:3, 4:5, 5:4, 9:16, 16:9, 21:9

quality

enum<string>

Quality of the generated image, default is 1K

Available options: 1K

image_urls

string<uri>[]

Reference image URL list for image-to-image and image editing functions

Note:

Maximum number of input images per request: 14
Image size: not exceeding 20MB
Supported file formats: .jpeg, .jpg, .png, .webp
Image URLs must be directly accessible by the server, or the image URL should directly download when accessed (typically these URLs end with image file extensions, such as .png, .jpg)

Example:

[
  "https://example.com/image1.png",
  "https://example.com/image2.png"
]

model_params

object

Model extension parameters

Show child attributes

model_params.thinking_level

enum<string>

Thinking level, controls the depth of reasoning the model performs before generating images, defaults to auto

auto: Automatically selects thinking level
min: Minimal reasoning, fastest
high: Deep reasoning, best quality

Available options: auto, min, high

Example:"auto"

callback_url

string<uri>

HTTPS callback address after task completion

Callback Timing:

Triggered when task is completed, failed, or cancelled
Sent after billing confirmation is completed

Security Restrictions:

Only HTTPS protocol is supported
Callback to internal IP addresses is prohibited (127.0.0.1, 10.x.x.x, 172.16-31.x.x, 192.168.x.x, etc.)
URL length must not exceed 2048 characters

Callback Mechanism:

Timeout: 10 seconds
Maximum 3 retries on failure (retries after 1 second/2 seconds/4 seconds)
Callback response body format is consistent with the task query API response format
Callback address returning 2xx status code is considered successful, other status codes will trigger retry

Example:"https://your-domain.com/webhooks/image-task-completed"

Response

200 - application/json

Image generation task created successfully

created

integer

Task creation timestamp

Example:1757165031

string

Task ID

Example:"task-unified-1757165031-uyujaw3d"

model

string

Actual model name used

Example:"gemini-3.1-flash-lite-image"

object

enum<string>

Specific task type

Available options: image.generation.task

progress

integer

Task progress percentage (0-100)

Required range: 0 <= x <= 100

Example:0

status

enum<string>

Task status

Available options: pending, processing, completed, failed

Example:"pending"

task_info

object

Asynchronous task information

Show child attributes

task_info.can_cancel

boolean

Whether the task can be cancelled

Example:true

task_info.estimated_time

integer

Estimated completion time (seconds)

Required range: x >= 0

Example:45

type

enum<string>

Task output type

Available options: text, image, audio, video

Example:"image"

usage

object

Usage and billing information

Show child attributes

usage.billing_rule

enum<string>

Billing rule

Available options: per_call, per_token, per_second

Example:"per_call"

usage.credits_reserved

number

Estimated credits consumed

Required range: x >= 0

Example:8.7

usage.user_group

enum<string>

User group category

Available options: default, vip

Example:"default"

Nanobanana 2 Lite Beta Image Generation