THE CRUNCH
Black Forest Labs has released FLUX 3 Image Klein, an open-weights image model that covers text-to-image generation, image editing and generation guided by up to ten reference images. It supports native 4K output, pixel-accurate editing and bounding boxes for placing elements, and an INT8 build runs on NVIDIA GPUs with just 8 GB of VRAM, generating an image in under 9 seconds on an RTX 4070.
The model has 5.6 billion parameters, 38 percent fewer than the 9 billion of its predecessor FLUX.2 [klein], yet Black Forest Labs reports it gains 91 Elo points over that model in internal testing. The company also says it scores the highest Elo ratings among all open models, ahead of closed competitors including Ideogram V4.5 and its own FLUX.2 [pro], though those figures come from the company's own benchmarks.
The weights ship under the FLUX Kommunity License, which allows free commercial use for companies making under $5 million annually. Beyond running locally through ComfyUI and Diffusers, the model is available via the BFL API at $0.009 per 1,000 images, as a Playground, and on Hugging Face Spaces. LoRA training, a lightweight method for customising a model, is supported from day one through the Ostris AI Toolkit and NVIDIA NeMo AutoModel.