Grok Image API

xAI image generation API for text-to-image and image-to-image workflows

Overview

Grok Image is an xAI image model for text-to-image generation and single-reference image-to-image workflows. Use this page when you are ready to call the API after trying the model in the APIXO playground.

Capability	Value
Model ID	grok-image
Modes	text-to-image, image-to-image
Prompt length	1-5000 characters
Reference images	1 URL for image-to-image
Aspect ratios	1:1, 3:2, 2:3 for text-to-image
Output	Image URL in resultJson.resultUrls

Endpoint and authentication

Base URL:

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

Method	Endpoint	Purpose
POST	/generateTask/grok-image	Submit a generation task
GET	/statusTask/grok-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

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

curl -X POST "https://api.apixo.ai/api/v1/generateTask/grok-image" \
  -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",
      "aspect_ratio": "3:2"
    }
  }'

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/grok-image?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://file.apixo.ai/xxx.png\"]}",
    "createTime": 1767965610929,
    "completeTime": 1767965635929,
    "costTime": 25000
  }
}

Failed response:

{
  "code": 200,
  "message": "success",
  "data": {
    "taskId": "task_12345678",
    "state": "failed",
    "failCode": "SensitiveContent",
    "failMsg": "Content violates provider policy, please adjust the prompt",
    "createTime": 1767965610929,
    "completeTime": 1767965620132,
    "costTime": 9039
  }
}

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 serene mountain landscape at dawn",
    "aspect_ratio": "2:3"
  }
}

Image-to-image

{
  "request_type": "async",
  "input": {
    "mode": "image-to-image",
    "prompt": "turn this photo into a cinematic portrait",
    "image_urls": [
      "https://example.com/ref.png"
    ]
  }
}

Parameters

request_type · string · default: "async"

Result delivery mode. Omit this field or use async for polling with statusTask, or use callback for webhook delivery.

callback_url · string

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

input · object · required

Grok Image 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. Supports 1-5000 characters. Empty prompts are rejected.

aspect_ratio · string · default: "1:1"

Output aspect ratio for text-to-image. Supported values: 1:1, 3:2, 2:3. This parameter is not forwarded for image-to-image.

image_urls · string[]

Reference image URLs. Required for image-to-image. Supports exactly 1 URL. The URL must be public and each array item must be a non-empty string.

Response format

Submit task response

POST /generateTask/grok-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 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 completion.

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/grok-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",
      "prompt": "a clean product photo of wireless earbuds on soft stone",
      "aspect_ratio": "1:1"
    }
  }'

Callback delivery uses the same final payload shape as the status response. See Webhooks for delivery requirements and retry behavior.

Billing

Grok Image is billed per generated image. Both supported modes use the same APIXO public price.

Mode	APIXO price
text-to-image	$0.10 / image
image-to-image	$0.10 / image

For current route and market comparison pricing, see Pricing.

Latency and polling

Actual latency may vary by prompt complexity, reference image access, provider queue load, and result storage time.

Mode	Typical generation time	Recommended first poll	Poll interval
text-to-image	About 25s on average	15s after task creation	3s
image-to-image	About 25s on average	15s after task creation	3s

For high-concurrency production workloads, use callback mode to avoid frequent polling.

Result URLs are valid for 15 days. Download and store important outputs promptly.

Prompts can be written in English or Chinese. More specific scene, style, lighting, and composition details usually produce better results. Output is PNG by default; if you need transparency, describe that requirement in the prompt.

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, missing mode, missing prompt, invalid aspect_ratio, malformed image_urls, or inaccessible image URL	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
429	Rate limit or concurrency limit reached	Retry with exponential backoff
500	Internal error or unknown task failure	Retry with backoff or contact support if it persists
502	Upstream provider or network error	Retry with backoff

Validation notes

Parameter	Backend behavior
input.mode	Required for routing. Must be text-to-image or image-to-image.
input.prompt	Required string. Must not be empty and must not exceed 5000 characters.
input.aspect_ratio	Optional for text-to-image. Must be 1:1, 3:2, or 2:3 if provided. Defaults to 1:1 for text-to-image.
input.image_urls	Required and non-empty for image-to-image. Must be an array of strings and cannot contain more than 1 image.

Task failure codes

failCode is generated from APIXO’s mapped provider error. Common values include:

Fail code	Meaning	What to do
PromptInvalid	Prompt was invalid or rejected by the provider	Rewrite the prompt and retry
SensitiveContent	Prompt or input/output content was rejected by safety checks	Change the prompt or reference image
ImageFormatIncorrect	Reference image format could not be processed	Use a public, direct image URL in a common image format
RateLimited	Provider rate limit was reached	Retry with exponential backoff
Timeout	Provider timeout	Retry later or use callback mode
Unknown error	Provider returned an unmapped failure	Retry with backoff or contact support with the taskId

See Error Codes for the full error reference.

Related links

• Generation API Overview
• Image Models
• Generate Task
• Status Task
• Webhooks
• Error Codes
• Parameter Specification
• Routing Strategies
• Try Grok Image in the APIXO Playground
• Pricing