Black Forest Labs (BFL) released FLUX 3 Image Klein on Wednesday, a 5.6 billion parameter open weights model for text-to-image generation, image editing, and multi-reference generation with support for up to 10 reference images. The model shares core capabilities with the full FLUX 3 Image model, including native 4K generation, pixel-perfect editing, and bounding box controls for element placement.
FLUX 3 Image Klein builds on FLUX 3's shared learnings across images, video, and audio. Images contribute spatial detail, video adds motion and physical dynamics, and audio provides information about events and interactions. Together, these signals help the model generate images that feel grounded in the real world rather than synthetic.
The release includes a base model for fine-tuning and a step-distilled model for low-latency generation, along with FP8, INT8, and NVFP4 builds developed with NVIDIA support, all under the FLUX Kommunity License. In internal evaluations, FLUX 3 Image Klein ranks first in text-to-image, multi-reference generation, and image editing, ahead of larger open weights models and even closed models like Ideogram V4.5 and FLUX.2 [pro].
At 5.6B parameters, it is the smallest open model in the comparison, against 7B for Qwen-Image 2.1 and 12.9B for Krea 2. Compared with FLUX.2 [klein] 9B, it gains 91 Elo in text-to-image and 70 in image editing. The model is available through the BFL API and weights can be downloaded for local deployment.