Qwen 2 Image API

Qwen 2 text-to-image API with standard and pro generation modes

Overview

Qwen 2 Image is an asynchronous text-to-image API. It supports standard and pro generation modes, multiple aspect ratios, prompt extension, optional negative prompts, and up to 6 images per task.

Capability	Value
Model ID	qwen-2-image
Modes	text-to-image, text-to-image-pro
Default mode	text-to-image
Prompt length	1-800 characters
Negative prompt	Optional, up to 500 characters
Images per task	num_images defaults to 1; range 1-6
Aspect ratios	1:1, 3:4, 4:3, 9:16, 16:9
Prompt extension	prompt_extend, default true
Watermark	watermark, default false

Endpoint and authentication

Base URL:

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

Method	Endpoint	Purpose
POST	/generateTask/qwen-2-image	Submit a text-to-image task
GET	/statusTask/qwen-2-image?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

curl -X POST "https://api.apixo.ai/api/v1/generateTask/qwen-2-image" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "request_type": "async",
    "input": {
      "mode": "text-to-image-pro",
      "prompt": "a premium poster for a bookstore event, crisp typography, elegant layout",
      "negative_prompt": "blurry text, distorted letters, low resolution",
      "aspect_ratio": "16:9",
      "num_images": 2,
      "prompt_extend": true,
      "watermark": false
    }
  }'

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/qwen-2-image?taskId=task_12345678" \
  -H "Authorization: Bearer YOUR_API_KEY"

Success response:

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

Parse resultJson after state becomes success:

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

Request body

Standard text-to-image

{
  "request_type": "async",
  "input": {
    "mode": "text-to-image",
    "prompt": "a minimalist product poster for wireless earbuds, clean layout",
    "aspect_ratio": "4:3",
    "num_images": 1,
    "prompt_extend": true,
    "watermark": false
  }
}

Pro text-to-image

{
  "request_type": "callback",
  "callback_url": "https://your-server.com/webhooks/apixo",
  "input": {
    "mode": "text-to-image-pro",
    "prompt": "a high-end brand key visual with readable headline text and premium lighting",
    "negative_prompt": "blurred typography, misspelled words, jagged edges",
    "aspect_ratio": "9:16",
    "num_images": 2,
    "seed": 123456
  }
}

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 callback URL that can receive the final task payload. See Webhooks.

input · object · required

Qwen 2 Image input parameters.

Show properties

mode · string · default: "text-to-image"

Generation mode. Supported values: text-to-image, text-to-image-pro. If omitted, the backend defaults to text-to-image.

prompt · string · required

Prompt text. Must be a non-empty string and cannot exceed 800 characters.

negative_prompt · string

Optional negative prompt. Maximum length is 500 characters.

aspect_ratio · string · default: "1:1"

Output aspect ratio. Supported values: 1:1, 3:4, 4:3, 9:16, 16:9.

num_images · integer · default: "1"

Number of output images. Accepts integer or numeric string input. Supported range: 1-6.

prompt_extend · boolean · default: "true"

Whether to enable prompt extension.

watermark · boolean · default: "false"

Whether to add a watermark to generated images.

seed · integer

Optional random seed. Supported range: 0-2147483647.

Response format

Submit task response

POST /generateTask/qwen-2-image 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: pending, processing, success, or failed.

resultJson · string

JSON string containing generated image URLs in resultUrls. 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 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/qwen-2-image" \
  -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": "text-to-image-pro",
      "prompt": "a premium campaign poster with readable headline text",
      "aspect_ratio": "16:9",
      "num_images": 1
    }
  }'

See Webhooks for delivery requirements and retry behavior.

Billing

Qwen 2 Image is billed per generated image.

Mode	APIXO price
text-to-image	$0.03 / image
text-to-image-pro	$0.07 / image

Billing behavior:

precharge = requested_num_images * unit_price_for_mode
final_charge = successful_images * unit_price_for_mode
refund = precharge - final_charge (if partial failure)

For current route and market comparison pricing, see Pricing.

Latency and polling

Qwen 2 Image tasks are asynchronous. Actual latency varies by prompt complexity, requested image count, and queue load.

Use case	Recommended first poll	Poll interval
Standard generation	10s after task creation	5s-10s
Pro mode or multiple images	10s-15s after task creation	5s-10s

For production queues or batches, use callback mode to avoid frequent polling.

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, parameter type, or value	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
404	Task not found	Verify the taskId and model ID
429	Rate limit or concurrency limit reached	Retry with exponential backoff
500	Server or unmapped model error	Retry with backoff
502	Model service error	Retry with backoff
504	Model service timeout	Retry or use callback mode for long-running jobs

Request validation

Condition	Backend behavior
Invalid mode	Returns Invalid mode type. Supported: text-to-image, text-to-image-pro
Missing or empty prompt	Returns a missing-parameter or validation error
Prompt exceeds 800 characters	Returns a length error
Invalid num_images	Returns The parameter {{num_images}} must be between 1 and 6.
Invalid aspect_ratio	Returns the supported aspect-ratio list
Invalid prompt_extend or watermark	Returns a boolean type error
Invalid seed	Returns the supported seed range

See Error Codes for the full error reference.

Related links

• Generation API Overview
• Image Models
• Generate Task
• Status Task
• Webhooks
• Error Codes
• Parameter Specification
• Pricing