Flux.2

What is Flux.2?#

Flux.2 is Black Forest Labs' December 2025 image model and the latest evolution of the Flux line. On Unifically it is exposed as three variants on the same /v1/tasks endpoint: Flex (with explicit diffusion controls), Pro (the balanced default), and Max (with an extra 5:4 aspect ratio). All three accept the same prompt-and-references core: an optional reference list of up to ten images, seven aspect ratios from 21:9 through 9:21, and resolutions at 0.6, 1, 2, or 4 megapixels. Currently the strongest open-model lineup for production stills.

Key features of Flux.2#

Three variants on the same endpoint

Flex, Pro, and Max share a request shape. Switch model identifiers (`flux.2-flex`, `flux.2-pro`, `flux.2-max`) to swap between explicit diffusion controls, balanced production runs, and extended aspect ratios.

Up to 4MP output

Resolution selector picks 0.6, 1, 2, or 4 megapixels. Useful for hero stills that need to survive crop, zoom, or high-DPI display without an upscale step.

Reference images on all variants

Pass up to ten URLs in `image_urls` on any variant. Useful for product references, mood boards, and brand-locked sequences without dropping to a separate edit endpoint.

Cinematic aspect ratio range

Shared ratios cover 21:9 ultrawide, 16:9 widescreen, 4:3 standard, 1:1 square, 3:4 portrait, 9:16 vertical, and 9:21 tall. Max adds 5:4 for editorial cover work.

Diffusion controls in Flex

Flex exposes `steps` (1–50) and `guidance` (1.5–10) for repeatable behaviour while you sweep settings. Useful for concept art and look development.

Best for#

Variants#

Flux.2 has three variants on the same API. They share the prompt-and-references core, but each exposes a slightly different control surface.

Flex#

Explicit diffusion controls. steps and guidance are first-class parameters. Use it when you are tuning a look (concept art, mood iteration) and want repeatable behaviour as you sweep settings.

Pro#

The balanced everyday variant. Same seven aspect ratios as Flex, no manual diffusion controls, faster per call. Default choice for marketing stills and reference-driven jobs.

Max#

Same core, with an extra 5:4 aspect ratio for editorial cover work. Use it when the brief is cinematic key art or anything that won't fit a standard ratio without a crop.

Use cases#

Tune a concept-art look on Flex by sweeping steps and guidance until the rendered material matches your reference; lock the seed and roll the same prompt onto Pro for the production batch. Build a marketing still set across the full ratio range (21:9 banner, 16:9 landing, 1:1 feed, 9:16 reel) on Pro from one prompt. Use Max for editorial cover work where the 5:4 ratio is the brief. Run high-volume reference-driven design (mood boards, product flat-lays) by passing up to ten references on any variant.

API examples#

Call Flux.2 from any language by POSTing to /v1/tasks. Full parameter docs live at docs.unifically.com/models/image/flux/flux.2-pro.

curl -X POST https://api.unifically.com/v1/tasks \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{
    "model": "black-forest-labs/flux.2-pro",
    "input": {
      "prompt": "A photorealistic portrait of a woman in golden hour light",
      "aspect_ratio": "9:16",
      "resolution": "2mp"
    }
  }'

Successful submission returns a task_id. Poll GET /v1/tasks/<task_id> or set a callback_url on the request to receive the finished result.