In brief
- Black Forest Labs released the weights of FLUX 3 Image Klein, an open model for generating and editing images.
- Free download under the FLUX Kommunity License, or the API from $0.009 per 1K image.
- According to the company, the generator runs on a consumer GPU with 8GB. The prompt expander needs more memory.
Black Forest Labs released FLUX 3 Image Klein, a 5.6B-parameter open-weights model for image generation, editing and multi-reference composition with up to 10 images.
AI Desk · Published October 16, 2026
First look: this report is based on the official announcement and documentation of Black Forest Labs and has not yet been tested hands-on by Maitz.
The company announced the release on October 15, 2026, on its blog. It is the second open-weights release in the FLUX 3 family, after FLUX 3 Action.
What is new in FLUX 3 Image Klein?
One model handles three jobs: text-to-image, instruction-based editing, and combining several reference images into one. It supports resolutions up to 4K and bounding boxes.
There are two versions. The distilled one generates fast in 16 steps. The Base version, at 50 steps, is meant for fine-tuning, LoRA training and research. Both are on Hugging Face, along with FP8, INT8 and NVFP4 builds.
How does it work, and what does it need to run?
It expects full scene captions, not short prompts. So the company ships a separate model, flux-3-image-klein-pup, that expands a short request into a full caption. According to the docs, results are generic without it, and it adds about 28GB of GPU memory.
The generator weights take 11.2GB in BF16 and 5.6GB in FP8. The company says the INT8 build runs on GeForce RTX GPUs with as little as 8GB of VRAM, through ComfyUI or Diffusers.
The numbers: speed, price and license
| Detail | According to Black Forest Labs |
|---|---|
| Parameters | 5.6B, generator only |
| Speed | About 4 seconds per 1MP image on an RTX 5090, under 9 seconds on an RTX 4070 |
| Test setup | Distilled model, INT8 build, through ComfyUI, measured by NVIDIA |
| API price | $0.009 per image at 1K, $0.036 at 4K |
| License | FLUX Kommunity License, free commercial use under $5M annual revenue |
In internal evaluations, the company says the model ranks first in text-to-image, multi-reference generation and editing among open-weights models, including larger ones. It also gains 91 Elo in text-to-image and 70 in editing over FLUX.2 klein 9B.
Why does a small local image model matter?
A small model running locally keeps your images and files on your machine. You can also train your own style: per the docs, a LoRA on 20 images took about 4.5 hours on one GPU.
What we don’t know yet
- How well the model handles non-English text inside images. The announcement does not say.
- Whether the internal rankings hold up in independent tests. The company has not published a full method here.
- The commercial license terms for companies above $5M revenue. The company points to its sales team.
What it means for you
- Developers and creators: with an RTX card of at least 8GB, you can run the generator in its INT8 build in ComfyUI. The prompt expander the company recommends adds about 28GB of GPU memory. Without that much memory, use the API.
- Small businesses: the license allows free commercial use under $5M revenue. Read its terms before selling outputs.
- No suitable hardware: the company API starts at $0.009 per image, with nothing to install.
- More on AI tools: see our AI tools directory and our ChatGPT Images 2.5 review for a closed-model comparison.
More on Maitz
Sources
- Black Forest Labs: FLUX 3 Image Klein, open weights, 5.6B parameters, bfl.ai/blog, October 15, 2026
- Black Forest Labs: FLUX 3 Image Klein, bfl.ai/models
- BFL Docs: FLUX 3 Image Klein, specs, pricing, Diffusers and LoRA training, docs.bfl.ml
- Hugging Face: black-forest-labs/flux-3-image-klein Model Card, including the license section
- Verified: October 16, 2026
