FLUX.2 Klein 4B

FLUX.2 [klein] is Black Forest Labs' speed-focused image family, released January 15, 2026. The 4B variant generates and edits images in under a second on consumer GPUs (around 13GB VRAM), unifying text-to-image, single-reference editing, and multi-reference composition in a single checkpoint — a meaningful simplification over pipelines that swap models per task.

The headline differentiator is licensing: the 4B model is released under Apache 2.0, permitting commercial use, redistribution, and derivatives without royalties — rare for a current-generation image model. The 9B sibling uses a non-commercial license instead. Limitations: Klein trades peak image quality for latency versus FLUX.2 [dev]/[max], and multi-reference editing caps at around four reference images.