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FLUX 2 Klein 9B

Text-to-Image • Black Forest Labs • Proxied

FLUX 2 Klein is Black Forest Labs' 9-billion parameter image generation model optimized for fast inference.

Model Info
Terms and Licenselink ↗
More informationlink ↗

Usage

TypeScript
const response = await env.AI.run(
  'black-forest-labs/flux-2-klein-9b',
  {
    prompt: 'A golden retriever puppy playing in autumn leaves',
  },
  {
    gateway: { id: 'default' },
  }
)
console.log(response)
Response 200 Simple Prompt

Examples

Detailed Scene — Complex scene with specific dimensions
TypeScript
const response = await env.AI.run(
  'black-forest-labs/flux-2-klein-9b',
  {
    prompt:
      'A Victorian-era street scene at dusk, gas lamps casting warm pools of light on cobblestones, horse-drawn carriages, and elegantly dressed pedestrians',
    width: 1024,
    height: 768,
  },
  {
    gateway: { id: 'default' },
  }
)
console.log(response)
Response 200 Detailed Scene
High Quality Generation — More inference steps for better quality
TypeScript
const response = await env.AI.run(
  'black-forest-labs/flux-2-klein-9b',
  {
    prompt:
      'A detailed oil painting portrait of a Renaissance nobleman with intricate lace collar',
    num_steps: 50,
    guidance: 7.5,
  },
  {
    gateway: { id: 'default' },
  }
)
console.log(response)
Response 200 High Quality Generation
Fast Draft — Quick generation with fewer steps
TypeScript
const response = await env.AI.run(
  'black-forest-labs/flux-2-klein-9b',
  {
    prompt: 'A simple sketch of a mountain landscape',
    num_steps: 10,
  },
  {
    gateway: { id: 'default' },
  }
)
console.log(response)
Response 200 Fast Draft
Reproducible Generation — Using a seed for consistent results
TypeScript
const response = await env.AI.run(
  'black-forest-labs/flux-2-klein-9b',
  {
    prompt:
      'A serene Japanese zen garden with raked sand patterns and a single bonsai tree',
    seed: 42,
    num_steps: 25,
  },
  {
    gateway: { id: 'default' },
  }
)
console.log(response)
Response 200 Reproducible Generation

Parameters

prompt
stringrequired
width
numberexclusiveMinimum: 0
height
numberexclusiveMinimum: 0
num_steps
numberexclusiveMinimum: 0
guidance
number
seed
number

API Schemas

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "type": "object",
  "properties": {
    "prompt": {
      "type": "string"
    },
    "width": {
      "type": "number",
      "exclusiveMinimum": 0
    },
    "height": {
      "type": "number",
      "exclusiveMinimum": 0
    },
    "num_steps": {
      "type": "number",
      "exclusiveMinimum": 0
    },
    "guidance": {
      "type": "number"
    },
    "seed": {
      "type": "number"
    }
  },
  "required": [
    "prompt"
  ],
  "additionalProperties": false
}