FLUX 3 Image Klein: A 5.6‑Billion‑Parameter Open‑Weight Model for Text‑to‑Image Generation

Black Forest Labs unveiled FLUX 3 Image Klein, a 5.6‑billion‑parameter open‑weight model designed for text‑to‑image generation, up to ten‑image reference synthesis, and pixel‑perfect editing. It shares the full FLUX 3 Image’s native 4K output, bounding‑box control for placing or confining edits, and a foundation built from images, video, and audio that makes generated scenes feel grounded in reality.

Performance and Size

In internal tests, FLUX 3 Image Klein ranked first in text‑to‑image quality, multi‑reference generation and image editing, outperforming larger open models and even closed‑source competitors like Ideogram V4.5 and FLUX.2 [pro].

FLUX 3 Image Klein is released as open weights and through the BFL API, with a base checkpoint for fine‑tuning and a step‑distilled checkpoint for low‑latency use. The weights are licensed under the FLUX Kommunity License, allowing free commercial use for entities earning under $5 million per year. Safety measures include dataset filters, targeted fine‑tuning, and external red‑team evaluation by Cinder, which showed fewer vulnerabilities than comparable open‑weight models. The model is available on Hugging Face, ComfyUI, Diffusers, and other frameworks, and is supported by NVIDIA’s accelerated platform for fast local deployment.