Black Forest Labs· FAST

Flux.2 Klein

The cheap, fast one — for the ninety drafts before the good one.

Generate with Flux.2 Klein (4B) from Black Forest Labs. Built for speed and cost, across nine aspect ratios, so you can iterate on a composition before spending on a flagship model.

Generate with Flux.2 Klein

Pay per image. No seat, no subscription.

What it accepts

Read straight off the generator's own model registry, so this page and the thing that runs your prompt can never disagree.

Model: black-forest-labs/flux.2-klein-4b
Aspect ratios: 9 — auto, 1:1, 3:2, 2:3, 16:9, 9:16…
Reference images: up to 4 per generation
Images per call: 1
Price: the same at every size

What Flux.2 Klein is for

Finding the composition. Run twenty, pick one, then re-run that prompt on a flagship model.
Working inside a budget, where the cost of a bad generation matters more than the ceiling of a good one.
Quick visual notes in the middle of other work, where waiting breaks your train of thought.

When not to use it

Once the prompt is right, run it again on Flux.2 Max for the finished frame.

Flux.2 Max

Every image model on Clear Cortex

One account, one pot of credit, all 7. Switch model between generations without losing your prompt.

Model	Maker	Max res	Ratios	Refs
Nano Banana 2	Google	4K	14	14
Nano Banana Pro	Google	4K	10	14
GPT Image 2	OpenAI	—	9	16
Seedream 4.5	ByteDance	4K	18	14
Flux.2 Klein	Black Forest Labs	—	9	4
Flux.2 Pro	Black Forest Labs	—	9	8
Flux.2 Max	Black Forest Labs	—	9	8

A dash under “Max res” means the model has no resolution setting to choose — it returns its own native size — not that it is limited to a small one. “Text in image” marks the model with per-tier quality control and a background setting — GPT Image 2 — which is the one built for legible type and clean cut-outs.

Try Flux.2 Klein now

One login, one invoice, 7 image models. You pay for the images you make, not for a seat you might not use.

Open the image studio