Nano Banana 2

Overview

Nano Banana 2 is a high-quality image generation model for text-to-image creation and reference-guided image generation. Use this page when you are ready to call the API after trying the model in the APIXO playground.

Capability	Value
Model ID	`nano-banana-2`
Modes	`text-to-image`, `image-to-image`
Prompt length	1-20000 characters
Reference images	Required for `image-to-image`; up to 14 URLs
Aspect ratios	`auto`, `1:1`, `1:4`, `4:1`, `1:8`, `3:2`, `2:3`, `3:4`, `4:3`, `4:5`, `5:4`, `8:1`, `9:16`, `16:9`, `21:9`
Resolution tiers	`1k`, `2k`, `4k`
Output formats	`png`, `jpeg`, `jpg`

Endpoint and authentication

Base URL:

https://api.apixo.ai/api/v1

Method	Endpoint	Purpose
`POST`	`/generateTask/nano-banana-2`	Submit a generation task
`GET`	`/statusTask/nano-banana-2?taskId={taskId}`	Poll task status and retrieve results

All requests require your APIXO API key:

Authorization: Bearer YOUR_API_KEY

Submit requests also require:

Content-Type: application/json

Copy-paste async quickstart

This minimal request submits a text-to-image task and returns a taskId.

curl -X POST "https://api.apixo.ai/api/v1/generateTask/nano-banana-2" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "request_type": "async",
    "input": {
      "mode": "text-to-image",
      "prompt": "a cozy cyberpunk cafe with neon lights and rain-soaked streets",
      "aspect_ratio": "3:2",
      "resolution": "2k"
    }
  }'

Successful response:

{
  "code": 200,
  "message": "success",
  "data": {
    "taskId": "task_12345678"
  }
}

Save the taskId; you need it to poll for the final result.

Poll for result

curl -X GET "https://api.apixo.ai/api/v1/statusTask/nano-banana-2?taskId=task_12345678" \
  -H "Authorization: Bearer YOUR_API_KEY"

Processing response:

{
  "code": 200,
  "message": "success",
  "data": {
    "taskId": "task_12345678",
    "state": "processing",
    "createTime": 1767965610929
  }
}

Success response:

{
  "code": 200,
  "message": "success",
  "data": {
    "taskId": "task_12345678",
    "state": "success",
    "resultJson": "{\"resultUrls\":[\"https://r2.apixo.ai/xxx.png\"]}",
    "createTime": 1767965610929,
    "completeTime": 1767965652317,
    "costTime": 41388
  }
}

Failed response:

{
  "code": 200,
  "message": "success",
  "data": {
    "taskId": "task_12345678",
    "state": "failed",
    "failCode": "SensitiveContent",
    "failMsg": "Content violates safety policy, please adjust the prompt",
    "createTime": 1767965610929,
    "completeTime": 1767965620132
  }
}

Parse resultJson after state becomes success:

const payload = JSON.parse(data.resultJson);
const imageUrls = payload.resultUrls;

Request body

Text-to-image

{
  "request_type": "async",
  "input": {
    "mode": "text-to-image",
    "prompt": "a fox in watercolor style",
    "aspect_ratio": "16:9",
    "resolution": "2k",
    "output_format": "png",
    "google_search": false
  }
}

Image-to-image

{
  "request_type": "async",
  "input": {
    "mode": "image-to-image",
    "prompt": "make this scene look like sunrise with warm golden light",
    "image_urls": [
      "https://example.com/source.png"
    ],
    "aspect_ratio": "4:5",
    "resolution": "4k",
    "output_format": "jpeg",
    "google_search": false
  }
}

Parameters

request_type

string

default:"async"

required

Result delivery mode. Use async for polling with statusTask, or callback for webhook delivery.

callback_url

string

Required when request_type is callback. Must be a public HTTPS URL that can receive the final task payload. See Webhooks.

input

object

required

Nano Banana 2 input parameters.

Show properties

mode

string

required

Generation mode. Supported values: text-to-image, image-to-image.

prompt

string

required

Text prompt describing the desired image or edit. Leading and trailing whitespace is ignored for validation. Supports 1-20000 characters.

image_urls

string[]

Reference image URLs. Required for image-to-image; provide 1-14 public, directly fetchable image URLs.

aspect_ratio

string

required

Output aspect ratio. Supported values: auto, 1:1, 1:4, 4:1, 1:8, 3:2, 2:3, 3:4, 4:3, 4:5, 5:4, 8:1, 9:16, 16:9, 21:9.

resolution

string

required

Output resolution tier. Supported values: 1k, 2k, 4k. The API accepts either lowercase or uppercase values and normalizes them for the selected route.

output_format

string

default:"png"

Output image format. Supported values: png, jpeg, jpg. Use jpeg for the JPEG format; jpg is accepted as an alias.

google_search

boolean

default:"false"

Enables web search context when supported by the active route. Defaults to false.

aspect_ratio and resolution are required. auto is accepted for aspect_ratio; on some routes it lets the upstream service choose the default framing.

Response format

Submit task response

POST /generateTask/nano-banana-2 returns a task ID when the task is accepted:

code

integer

API status code. 200 means the task was accepted.

message

string

Human-readable status message.

data.taskId

string

Unique task identifier used with the status endpoint.

Status response fields

taskId

string

Unique task identifier.

state

string

Current task state: processing, success, or failed.

resultJson

string

JSON string containing the generated image URLs. Present when state is success.

failCode

string

Machine-readable failure code. Present when state is failed.

failMsg

string

Human-readable failure message. Present when state is failed.

createTime

integer

Task creation timestamp in Unix milliseconds.

completeTime

integer

Task completion timestamp in Unix milliseconds. Present after completion.

costTime

integer

Processing duration in milliseconds. Present after successful completion when available.

Webhook callback mode

Use callback mode when your backend should receive the final result automatically instead of polling.

curl -X POST "https://api.apixo.ai/api/v1/generateTask/nano-banana-2" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "request_type": "callback",
    "callback_url": "https://your-server.com/webhooks/apixo",
    "input": {
      "mode": "image-to-image",
      "prompt": "turn this product photo into a polished studio ad",
      "image_urls": [
        "https://example.com/product.png"
      ],
      "aspect_ratio": "1:1",
      "resolution": "2k",
      "output_format": "png"
    }
  }'

See Webhooks for delivery requirements and retry behavior.

Billing

Nano Banana 2 is billed per generated image. The selected resolution determines the unit price.

Resolution	APIXO price
`1k`	`$0.05 / image`
`2k`	`$0.08 / image`
`4k`	`$0.12 / image`

For current route and market comparison pricing, see Pricing.

Latency and polling

Actual latency may vary by prompt complexity, reference image accessibility, selected resolution, route health, and current queue load. The backend returns costTime in milliseconds after completion when timing data is available.

Stage	Guidance
First poll	Wait 10s-20s after task creation before the first status request
Poll interval	Poll every 10s while `state` is `processing`
Production delivery	Use callback mode for high-concurrency workloads

Result URLs are available for 15 days by default. Download and store important outputs promptly.

Rate limits and concurrency can vary by account, API key, and route. If you receive 429, slow down requests and retry with backoff. For account-level details, see System APIs.

Errors and troubleshooting

HTTP errors

Code	Meaning	What to do
`400`	Invalid request body, mode, parameter, or image URL shape	Fix the request before retrying
`401`	Missing or invalid API key	Check the `Authorization` header
`402`	Insufficient balance or quota	Add balance or switch account/key
`403`	Key or route cannot access the model	Check permissions and route strategy
`429`	Rate limit or concurrency limit reached	Retry with exponential backoff
`500`	Server or unmapped upstream error	Retry with backoff
`502`	Upstream service error	Retry with backoff
`504`	Upstream timeout	Retry or use callback mode for long-running jobs

Task failure codes

Fail code	Meaning	What to do
`PromptInvalid`	Prompt was invalid or rejected upstream	Revise the prompt
`SensitiveContent`	Prompt or output violated safety policy	Change the prompt or reference image
`ImageFormatIncorrect`	A reference image could not be accepted upstream	Use a public, direct image URL in a common image format
`MissingParameter`	A required upstream parameter was missing	Check `mode`, `prompt`, `aspect_ratio`, `resolution`, and `image_urls`
`RateLimited`	Upstream rate limit was reached	Retry with backoff
`Timeout`	Upstream timeout	Retry, reduce input complexity, or use callback mode
`Unknown error`	Upstream failure did not match a known rule	Retry with backoff or contact support with the `taskId`

See Error Codes for the full error reference.

Getting Started

Image Models

Video Models

Audio Models

Nano Banana 2

Overview

Endpoint and authentication

Copy-paste async quickstart

Poll for result

Request body

Text-to-image

Image-to-image

Parameters

Response format

Submit task response

Status response fields

Webhook callback mode

Billing

Latency and polling

Errors and troubleshooting

HTTP errors

Task failure codes

Getting Started

Image Models

Video Models

Audio Models

Documentation Index

​Overview

​Endpoint and authentication

​Copy-paste async quickstart

​Poll for result

​Request body

​Text-to-image

​Image-to-image

​Parameters

​Response format

​Submit task response

​Status response fields

​Webhook callback mode

​Billing

​Latency and polling

​Errors and troubleshooting

​HTTP errors

​Task failure codes

​Related links

Overview

Endpoint and authentication

Copy-paste async quickstart

Poll for result

Request body

Text-to-image

Image-to-image

Parameters

Response format

Submit task response

Status response fields

Webhook callback mode

Billing

Latency and polling

Errors and troubleshooting

HTTP errors

Task failure codes

Related links