Developers who need fast, cheap image generation can run the 4B version free on modest hardware; the 9B weights are non-commercial.
Kenning's take
What it does
FLUX.2 [klein] is the smallest and fastest branch of Black Forest Labs FLUX.2, built for real-time image generation and editing. The 4B versions are released under Apache 2.0 and run in about 8 to 9GB of graphics memory, while the 9B versions use a non-commercial licence. They can be run locally, fine-tuned, or called through the BFL API.
- Sub-second generation on high-end GPUs
- 4B (Apache 2.0) and 9B variants
- Base versions for fine-tuning
- Image generation and editing
- Free online demo
Who it suits. Developers building real-time or high-volume image features, and people running models locally.
Key facts
- Category
- AI models
- Part of
- FLUX.2
- Made by
- Black Forest Labs
- Released
- 15 January 2026
- How to get it
- Open weights on Hugging Face; BFL API and Playground
- Works on
- open weights, API, web playground
- In the UK
- Yes
- Free plan
- 4B weights under Apache 2.0; 9B under non-commercial licence
- API price
- [klein] 4B from $0.014, 9B from $0.015 per image
FAQ
When was FLUX.2 [klein] released?
It was released on 15 January 2026, according to Puter developer docs.
Is FLUX.2 [klein] free?
The 4B versions are free under Apache 2.0, including commercial use. The 9B versions are non-commercial.
How much memory does FLUX.2 [klein] need?
About 8.4GB for the 4B model and 19.6GB for the 9B model, per Black Forest Labs.
Facts from the maker's own pages and the sources listed. Checked 2026-10-11.
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