Black Forest Labs · Image API

FLUX 2

flux-2

Flexible high-quality generation for photorealism, art direction, and production assets.

POST/v1/images/generations

Output count1–1

Reference imagesUp to 8

Resolution tiers1MP · 2MP · 3MP · 4MP

Generation

Generate with FLUX 2

Use ImgRouter's unified request contract and this model ID. The example uses recommended defaults from the route's current parameter guide.

cURL

curl https://api.imgrouter.com/v1/images/generations \
  -H "Authorization: Bearer $IMGROUTER_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: flux-2-generate-001" \
  -d '{
  "model": "flux-2",
  "prompt": "Editorial product photograph, precise materials, soft studio light",
  "size": "1:1",
  "resolution": "2MP",
  "n": 1,
  "output_format": "jpeg"
}'

Request body

modelstring · requiredUse flux-2.

promptstring · requiredGeneration or editing instruction between 1 and 5,000 characters.

sizestringSupported values: auto, 1:1, 4:3, 3:4, 16:9, 9:16, 3:2, 2:3, 21:9, 9:21.

resolutionstringSupported values: 1MP, 2MP, 3MP, 4MP.

ninteger · 1–1Number of output images. Defaults to 1 and cannot exceed 1.

output_formatstringSupported values: jpeg, png, webp.

reference_imagesstring[] · max 8Public HTTPS source images. Send this field to the edit endpoint.

Controls

Supported options

Aspect ratio or size

auto1:14:33:416:99:163:22:321:99:21

Resolution

1MP2MP3MP4MP

Output format

jpegpngwebp

Route notes

Uses megapixel resolution tiers rather than 1K/2K/4K.

Supports up to eight reference images, with a shared pixel budget across inputs and output.

One output image is produced per request.

Reference workflow

Edit with reference images

Send public HTTPS source images with the same core controls. This route accepts up to 8 reference images.

POST/v1/images/edits

cURL

curl https://api.imgrouter.com/v1/images/edits \
  -H "Authorization: Bearer $IMGROUTER_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: flux-2-edit-001" \
  -d '{
  "model": "flux-2",
  "prompt": "Preserve the subject and composition. Change the scene to soft blue hour.",
  "size": "1:1",
  "resolution": "2MP",
  "n": 1,
  "output_format": "jpeg",
  "reference_images": [
    "https://example.com/reference.jpg"
  ]
}'

Describe both the intended change and the details that must remain consistent. Stable source URLs produce the most reliable edit requests.

Response

Read the completed output

Successful requests return completed image URLs and a request ID. Store the assets you need permanently; routed output URLs may expire.

200 · application/json

{
  "id": "req_01K4…",
  "object": "image.generation",
  "created": 1787424152,
  "data": [
    { "url": "https://static.imgrouter.com/images/req_01K4.webp" }
  ],
  "usage": { "images": 1 }
}

Use GET /v1/requests/{request_id} for reconciliation and GET /v1/balance for the authenticated key's current Credit position.