FLUX.2 [flex] - AnyFast

Key capabilities
Quick example
Parameters
Response

FLUX.2 [flex] is a highly configurable text-to-image generation model from Black Forest Labs, available through AnyFast. It offers fine-grained control over inference steps and guidance scale for design experts. The API is synchronous — it returns the generated image directly as base64-encoded data.

Key capabilities

Text-to-image — Generate images from text descriptions
Inference steps control — Adjust sampling steps (1–50) for speed vs. fidelity tradeoff
Guidance scale — Fine-tune prompt adherence (1.5–10)
High resolution — Supports up to 4MP output resolution
Reproducible — Use seed for deterministic generation

Quick example

curl https://www.anyfast.ai/v1/images/generations \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "flux-2-flex",
    "prompt": "A cute baby polar bear",
    "size": "1024x1024",
    "inference_steps": 30,
    "guidance_scale": 7.5
  }'

Parameters

Parameter	Type	Required	Description
`model`	string	Yes	Must be `flux-2-flex`
`prompt`	string	Yes	Text description of the image
`n`	integer	No	Number of images (1–4). Default: `1`
`size`	string	No	Output size, e.g. `1024x1024`. Supports up to 4MP
`inference_steps`	integer	No	Sampling steps (1–50). Low (6–20) for fast prototyping, high (40–50) for max fidelity
`guidance_scale`	number	No	Guidance scale (1.5–10). Higher = more prompt-faithful
`output_format`	string	No	`jpeg` or `png`
`seed`	integer	No	Random seed for reproducibility

Response

Field	Description
`data[].b64_json`	Base64-encoded image data
`created`	Unix timestamp

API Reference

View the interactive API playground for FLUX.2 [flex].

FLUX.2 [pro]FLUX.1 Kontext [pro]