Flux 2 API — AI Image Generation API | Photorealistic, Free Credits

Provider

Black Forest Labs

Pricing

6–20 credits per image (~$0.012–$0.04)

Speed

3–8 seconds

Output

image

Quick Start

Send a request to the Flux 2 API:

bash

curl -X POST https://apiin.one/api/v1/images/generations \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "flux-2",
  "prompt": "A serene Japanese garden with cherry blossoms, koi pond, and wooden bridge, photorealistic",
  "aspect_ratio": "16:9",
  "type": "pro",
  "resolution": "1K"
}'

API Endpoint

POST/api/v1/images/generationsFlux 2

Send a POST request with your API key to generate content using Flux 2.

Headers

Header	Tür	Gerekli	Açıklama
`Authorization`	string	Gerekli	Bearer YOUR_API_KEY
`Content-Type`	string	Gerekli	application/json

Body Parameters

Parametre	Tür	Gerekli	Açıklama
`model`	string	Gerekli	Model identifier: "flux-2"
`prompt`	string	Gerekli	Text description of the image (3–5000 chars)
`aspect_ratio`	string	İsteğe Bağlı	Output aspect ratio (e.g. 1:1, 16:9, 9:16) (Varsayılan: 1:1)
`type`	string	İsteğe Bağlı	Generation mode: "pro" (higher quality) or "flex" (faster/cheaper) (Varsayılan: pro)
`resolution`	string	İsteğe Bağlı	Output resolution: "1K" or "2K" (Varsayılan: 1K)
`input_urls`	array	İsteğe Bağlı	Array of image URLs for image-to-image (max 8 images)

Example Request

json

{
  "model": "flux-2",
  "prompt": "A serene Japanese garden with cherry blossoms, koi pond, and wooden bridge, photorealistic",
  "aspect_ratio": "16:9",
  "type": "pro",
  "resolution": "1K"
}

Example Response

Successful task creation response.

{
  "code": 200,
  "message": "success",
  "data": {
    "task_id": "n41xxxx_flux2",
    "status": "IN_PROGRESS"
  }
}

Check Task Status

For asynchronous tasks, poll the status endpoint to check when your task is complete:

GET/api/v1/tasks/{task_id}Poll task status

Returns the current status of a generation task. Poll until status is 'completed' or 'failed'.

bash

curl https://apiin.one/api/v1/tasks/task_abc123 \
  -H "Authorization: Bearer aio_your_key"

Use Cases

✓Generate product mockups and marketing visuals from text descriptions
✓Create AI-generated artwork and illustrations for content
✓Build AI image generation features into your application
✓Produce photorealistic stock images on demand

API Tester

Test the Flux 2 API directly from your browser:

API AlanıPOST

Temel URL

Uç Nokta

Başlıklar

İstek Gövdesi

Error Codes

{
  "error": {
    "code": 400,
    "message": "Invalid parameters",
    "type": "invalid_request"
  }
}

Frequently Asked Questions

How much does the Flux 2 API cost?

Credits vary by mode and resolution. Pro mode at 1K costs ~10 credits, 2K costs ~20 credits. Flex mode at 1K costs ~6 credits. Free credits included on sign up.

What is the difference between Pro and Flex mode?

Pro mode produces higher quality results. Flex mode is faster and cheaper, suitable for rapid iteration. Set the "type" parameter to "pro" or "flex".

Can I use reference images?

Yes. Flux 2 supports image-to-image by providing up to 8 input image URLs via the "input_urls" parameter alongside your text prompt.

What resolutions are supported?

Flux 2 supports 1K and 2K resolution output. Set via the "resolution" parameter.

Is the Flux 2 API compatible with OpenAI?

Yes. API in One uses an OpenAI-compatible REST format. If you're already using the OpenAI Images API, switching to Flux 2 requires minimal code changes.