FLUX.2 [pro]

Text-to-Image • Black Forest Labs

black-forest-labs/flux-2-pro-preview

• Third-party

FLUX.2 [pro] Preview is Black Forest Labs' recommended default for production image generation and editing — tracks the latest [pro] weights with strong multi-reference support.

Usage

const response = await env.AI.run(
  'black-forest-labs/flux-2-pro-preview',
  {
    prompt:
      'A serene mountain landscape at golden hour, soft diffused light filtering through clouds',
    height: 1024,
    width: 1024,
  },
)
console.log(response)

curl https://api.cloudflare.com/client/v4/accounts/$CLOUDFLARE_ACCOUNT_ID/ai/run \
  --header "Authorization: Bearer $CLOUDFLARE_API_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "model": "black-forest-labs/flux-2-pro-preview",
  "input": {
    "prompt": "A serene mountain landscape at golden hour, soft diffused light filtering through clouds",
    "height": 1024,
    "width": 1024
  }
}'

{
  "state": "Completed",
  "result": {
    "image": "https://examples.aig.cloudflare.com/black-forest-labs/flux-2-pro-preview/simple-prompt.jpeg"
  },
  "gatewayMetadata": {
    "keySource": "Unified"
  }
}

Examples

<details>

<summary>Multi-Reference Editing — Multi-reference editing — combine two reference images in a single composition</summary>

const response = await env.AI.run(
  'black-forest-labs/flux-2-pro-preview',
  {
    prompt: 'Combine the subjects of these images into a single editorial fashion scene',
    input_images: [
      'https://replicate.delivery/xezq/jCypj4MeXYUiRyq7nfgm8z1OvFZF81wh4FznutDsZOuJz0YWA/tmp1iukn307.jpg',
      'https://replicate.delivery/xezq/0lxxNQSg3NabCZrDiQVAPGVmjP1Q2dd7TgYCOTfI9LpyZaMLA/tmp89gopylq.jpg',
    ],
  },
)
console.log(response)

curl https://api.cloudflare.com/client/v4/accounts/$CLOUDFLARE_ACCOUNT_ID/ai/run \
  --header "Authorization: Bearer $CLOUDFLARE_API_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "model": "black-forest-labs/flux-2-pro-preview",
  "input": {
    "prompt": "Combine the subjects of these images into a single editorial fashion scene",
    "input_images": [
      "https://replicate.delivery/xezq/jCypj4MeXYUiRyq7nfgm8z1OvFZF81wh4FznutDsZOuJz0YWA/tmp1iukn307.jpg",
      "https://replicate.delivery/xezq/0lxxNQSg3NabCZrDiQVAPGVmjP1Q2dd7TgYCOTfI9LpyZaMLA/tmp89gopylq.jpg"
    ]
  }
}'

{
  "state": "Completed",
  "result": {
    "image": "https://examples.aig.cloudflare.com/black-forest-labs/flux-2-pro-preview/multi-reference-editing.jpeg"
  },
  "gatewayMetadata": {
    "keySource": "Unified"
  }
}

</details>

<details>

<summary>Reproducible PNG Output — Seeded generation with PNG output for downstream editing pipelines</summary>

const response = await env.AI.run(
  'black-forest-labs/flux-2-pro-preview',
  { prompt: 'A pastel watercolor of a koi pond at sunrise', output_format: 'png', seed: 1337 },
)
console.log(response)

curl https://api.cloudflare.com/client/v4/accounts/$CLOUDFLARE_ACCOUNT_ID/ai/run \
  --header "Authorization: Bearer $CLOUDFLARE_API_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "model": "black-forest-labs/flux-2-pro-preview",
  "input": {
    "prompt": "A pastel watercolor of a koi pond at sunrise",
    "output_format": "png",
    "seed": 1337
  }
}'

{
  "state": "Completed",
  "result": {
    "image": "https://examples.aig.cloudflare.com/black-forest-labs/flux-2-pro-preview/reproducible-png-output.png"
  },
  "gatewayMetadata": {
    "keySource": "Unified"
  }
}

</details>

Parameters

prompt

stringrequiredText prompt for image generation or editing.

seed

integerminimum: -9007199254740991maximum: 9007199254740991Optional seed for reproducible generation.

width

integerminimum: 64maximum: 9007199254740991Width of the generated image in pixels (minimum 64). Omit to let BFL pick.

height

integerminimum: 64maximum: 9007199254740991Height of the generated image in pixels (minimum 64). Omit to let BFL pick.

safety_tolerance

integerminimum: 0maximum: 5Tolerance for input/output moderation. 0 is the strictest, 5 the most permissive. Defaults to 2.

output_format

stringenum: jpeg, png, webpOutput image format. Defaults to jpeg.

▶input_images[]

arraymaxItems: 8Up to 8 reference images for editing or multi-image composition. Each entry is an HTTPS URL or a data:image/...;base64,... URI.

image

stringformat: uriURL to the generated image

API Schemas (Raw)

Input Open Download

Output Open Download

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description: FLUX 3 Image Klein is Black Forest Labs' 5.6B-parameter image model for text-to-image, image editing, and multi-reference generation with up to 10 reference images. It supports native 4K output and bounding-box layout control. title: FLUX 3 Image Klein image: https://developers.cloudflare.com/og-docs.png

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