Flux 2 Klein: Sub-Second AI Image Generation
The fastest open-source AI image generator for real-time workflows
The fastest open-source AI image generator from Black Forest Labs. Generate and edit stunning 4K images with perfect text rendering in under half a second on consumer GPUs.
Generate with Flux 2 Klein
Results
What is Flux 2 Klein?
Flux 2 Klein is a compact, high-performance AI image generation model from Black Forest Labs, featuring 4B parameters with a rectified flow Transformer architecture. It delivers sub-second inference with just 4 steps.
With unified generation and editing capabilities, Flux 2 Klein supports text-to-image, image-to-image, and multi-reference workflows in a single model. The 4B version is fully open-source under Apache 2.0 license.
Why Choose Flux 2 Klein?
The fastest open-source AI image generator for real-time workflows
Sub-Second Generation
Generate high-quality images in under 0.5 seconds with just 4 inference steps. Perfect for real-time creative workflows, rapid prototyping, and interactive design tools.
Apache 2.0 Open Source
The 4B version is fully open-source under Apache 2.0 license. Download weights, deploy locally, fine-tune for your needs, and use commercially without restrictions.
Unified Generation & Editing
Single model supports text-to-image generation, image-to-image editing, and multi-reference consistency. No need to switch between different models.
4MP High Resolution
Generate images up to 4 megapixels (~2048×2048) with any aspect ratio. From minimum 64×64 to maximum 4MP, supporting all creative needs.
Multi-Reference Support
Use up to 4 reference images to maintain character consistency, style coherence, and product identity across multiple generations.
Perfect Text Rendering
Industry-leading text generation with proper kerning, alignment, and multilingual support. Ideal for UI mockups, infographics, and marketing materials.
Technical Specifications
Optimized for speed and accessibility
Model Parameters
Maximum Resolution
VRAM Required
Inference Steps
Reference Images
License
Use Cases
Perfect for designers, marketers, and developers
Rapid Prototyping
Test compositions, lighting, and styles quickly with sub-second feedback loops. Ideal for creative exploration and concept development.
- Quick Iterations
- Concept Art
- Style Testing
Marketing Content
Generate product visuals, brand assets, and campaign materials at scale. Multi-reference ensures brand consistency across all outputs.
- Product Shots
- Brand Assets
- Social Media
UI/UX Design
Create clean, readable mockups with perfect typography. Generate UI layouts, infographics, and design elements with precise text rendering.
- UI Mockups
- Infographics
- Design Elements
Simple 3-Step Workflow
From prompt to image in under a second
Enter Your Prompt
Describe your image using natural prose. Add reference images for style consistency.
AI Generates
Flux 2 Klein creates your image in under 0.5 seconds with just 4 inference steps.
Download & Use
Get your high-quality image ready for any project. Commercial use fully allowed.
Frequently Asked Questions
Flux 2 Klein is a compact, high-speed AI image generation model from Black Forest Labs. It uses a rectified flow Transformer architecture with 4B parameters, delivering sub-second image generation with just 4 inference steps.
Klein 4B is fully open-source under Apache 2.0, allowing commercial use. It requires ~13GB VRAM. Klein 9B has more parameters for higher fidelity but uses a non-commercial license and requires ~19-29GB VRAM.
For the 4B version, you need approximately 13GB VRAM. Consumer GPUs like RTX 3090 or RTX 4070 can run it efficiently. FP8 and NVFP4 quantization options reduce VRAM requirements further.
Yes, the Klein 4B version is under Apache 2.0 license, allowing full commercial use. You can use generated images for marketing, products, and any commercial purpose without restrictions.
Flux 2 Klein is significantly faster than SDXL and Flux Pro, generating images in under 0.5 seconds. It trades some fine detail for speed but maintains excellent quality for most use cases.
You can upload up to 4 reference images to maintain consistency in character likeness, style, or product identity across generations. The model blends these references according to your prompt.
Ready to Create with Flux 2 Klein?
Experience sub-second AI image generation with full commercial rights.