Black Forest Labs released FLUX 3 Image Klein, a 5.6-billion-parameter open-weights image model supporting native 4K output and precise spatial editing. The model runs locally on consumer GPUs with as little as 8 GB of VRAM. Under the FLUX Kommunity License, commercial use is free for businesses earning under $5 million annually, while API pricing starts at $0.009 per 1K image.
Model capabilities and features
- ▪Black Forest Labs' FLUX 3 Image Klein supports native 4K output, spatial controls driven by reference images, and bounding boxes for specifying element placement in image generation
- ▪Black Forest Labs released FLUX 3 Image Klein, a 5.6-billion-parameter open-weights image model for generation, editing, and reference-based visual customization
- ▪Black Forest Labs' FLUX 3 Image Klein supports up to ten reference images simultaneously for image generation and pixel-accurate editing workflows
Model availability and deployment options
- ▪Black Forest Labs released FLUX 3 Image Klein in a base version, a lower-latency distilled version, and compressed FP8, NVFP4, and INT8 versions
- ▪Black Forest Labs made FLUX 3 Image Klein available via its API, a web Playground, Hugging Face Spaces, and local execution frameworks including ComfyUI and Diffusers
- ▪Developers can fine-tune FLUX 3 Image Klein using Ostris AI Toolkit, vLLM-Omni, SGLang Diffusion, and Nvidia NeMo AutoModel
Performance and parameter efficiency evaluations
- ▪In Black Forest Labs internal evaluations, FLUX 3 Image Klein achieved the highest Elo ratings among open models, outscoring Qwen-Image 2.1, Ideogram 4.5, and FLUX.2 [pro]
- ▪Black Forest Labs reported that FLUX 3 Image Klein gained 91 Elo points over FLUX.2 [klein] while utilizing 38 percent fewer parameters than that model's 9 billion
Local hardware requirements and benchmark speeds
- ▪FLUX 3 Image Klein can run locally on consumer GPUs and laptops equipped with as little as 8 GB of video memory
- ▪On an Nvidia RTX 4070 GPU running the 16-step INT8 distilled version, FLUX 3 Image Klein took 8.9 seconds to generate a 1,024 x 1,024 image and 50.4 seconds at 2,048 x 2,048 resolution
- ▪On an Nvidia RTX 5090 GPU using the 16-step INT8 distilled version, FLUX 3 Image Klein generated a 1,024 x 1,024 image in 4.1 seconds and edited one in 7.2 seconds
API pricing structure
- ▪Black Forest Labs set FLUX 3 Image Klein API pricing at $0.008 per 768 x 768 image, $0.009 per 1K-resolution generation or edit, $0.014 for 2K, and $0.036 for 4K output
- ▪Black Forest Labs set identical API prices for image generation and image editing at each supported resolution for FLUX 3 Image Klein
FLUX Kommunity License commercial terms
- ▪The FLUX Kommunity License for FLUX 3 Action determines eligibility using gross annualized revenue combined across affiliates rather than individual project budgets
- ▪The FLUX Kommunity License grants free commercial use of FLUX 3 Image Klein under $5 million annual revenue; organizations over $5 million require a separate commercial self-hosting arrangement or hosted API
Safety testing and vulnerabilities
- ▪Black Forest Labs reported that FLUX 3 Image Klein demonstrated fewer safety vulnerabilities than other popular open-weights models
- ▪External partner Cinder evaluated both FLUX 3 Image Klein checkpoints for safety prior to the model's release following dataset filtering and post-training to limit harmful outputs
Training architecture and infrastructure
- ▪Black Forest Labs trained FLUX 3 Image Klein on Nvidia GB200 GPUs in an NVL72 system
- ▪Black Forest Labs incorporated shared training across images, video, and audio to help FLUX 3 Image Klein learn visual structure and physical behavior
Story comments
Loading comments…