Grok Voice 3.0
Build real-time conversational voice applications with streaming speech, configurable sessions, tools, and SIP phone integration.
FLUX 3 Image Klein
bfl.ai
Generate and edit images with downloadable weights, multiple references, bounding-box controls, and hosted API access.
Visit website
Pricing
Freemium
Available on
Web, API, Self-hosted, ComfyUI, Hugging Face Diffusers
Category
Ai Image Tools
What is FLUX 3 Image Klein?
FLUX 3 Image Klein is Black Forest Labs’ downloadable image generation and editing model. It creates images from text, modifies existing pictures, and combines visual references. Designers can explore visual assets, while developers can integrate generation into applications or run the model on their own infrastructure.
Two 5.6-billion-parameter variants serve different workflows: Distilled targets fast inference, while Base supports fine-tuning, LoRA training, and research. The hosted API serves Distilled.
Key features
Text-to-image generation and editing
Create images from written descriptions or provide an existing image with instructions describing the desired changes.
Up to ten reference images
Combine multiple visual references in one request to guide a composition using several source images.
Bounding-box layout controls
Specify element placement or confine edits to selected regions. Boxes use a normalized 0–1000 canvas with coordinates ordered as y_min, x_min, y_max, x_max.
Output up to 4K
Both Base and Distilled support image output up to 4K resolution.
Downloadable deployment options
Run weights through ComfyUI or Diffusers. FP8, INT8, and NVFP4 builds offer deployment choices for compatible hardware.
Who is it for?
Designers exploring compositions
Develop illustration or campaign concepts using reference images and planned element positions.
Creative teams revising assets
Request targeted changes to an existing visual while defining the intended editing area.
Developers building image products
Evaluate hosted generation or local deployment for an image creation application.
Researchers adapting visual styles
Explore Base-model fine-tuning or LoRA training for a specialized visual workflow within the license terms.
How to use FLUX 3 Image Klein
- Choose hosted API access or a local ComfyUI or Diffusers workflow.
- For hosted access, register a BFL account, confirm your email, add credits, and create a project-scoped API key.
- For local access, download the weights and configure the workflow. In Diffusers, run the separate prompt upsampler or supply a full scene caption.
- Prepare your description, reference images, and any bounding boxes.
- For hosted generation, submit to flux-3-image-klein and poll polling_url until the status is Ready. For local generation, run the configured workflow.
FLUX 3 Image Klein pricing
Freemium
Weights are available without license fees for permitted non-commercial use and qualifying commercial output generation. Hosted API access is paid per generated image, without subscription or seat fees. Uses outside the free license grant require separate licensing.
Hosted Klein API
USD 0.008–0.036 per generated image
Pay as you go using credits; no recurring subscription interval.
Generation and editing cost USD 0.008 at 768 × 768, USD 0.009 at 1K, USD 0.011 at 1.5K, USD 0.014 at 2K, and USD 0.036 at 4K. One credit equals USD 0.01.
What to know before you use it
- Diffusers does not run the prompt upsampler automatically. Running that separate model adds about 28 GB of GPU memory.
- Free commercial output generation under the FLUX Kommunity License requires combined gross annualized revenue with affiliates below USD 5 million, filtering or output review, and legally required AI disclosures. The license prohibits using the model, derivatives, or outputs to improve another AI model with similar functionality.
- BFL’s reported 8 GB VRAM configuration concerns the INT8 image generator on compatible NVIDIA GeForce RTX hardware. The separate prompt upsampler has additional memory requirements.
Frequently asked questions
Which variant should I choose?
Choose Distilled for fast generation and hosted API access. Choose Base for fine-tuning, LoRA training, or research, subject to the license.
Can I use generated images commercially?
Qualifying users can generate commercial outputs under the Kommunity License’s conditions. Its restriction on improving another AI model with similar functionality still applies. Uses outside the grant require separate permission or licensing.
Can I try it without building an integration?
BFL offers a browser Playground. API and Playground usage draw on account credits.