Flux AI Image Generator
Black Forest Labs' Flux is the leading open-source image generation model. From rapid prototyping with Flux Schnell to professional editing with Flux 2 Klein and Kontext — run every variant available on ComfyUI Web.
Flux AI on ComfyUI Web
Run Flux models directly in your browser. Pick a variant to start generating.
Flux Dev
Generate images with FLUX Dev endpoint.
FLUX.1 Schnell
Optimized for speed, this model generates images from text prompts quickly. A ~3x speedup over the original model with minimal quality loss.
FLUX.1 Kontext Dev
Fast endpoint for Flux Kontext. Specialized for precise image editing and manipulation through text prompts with pro-level editing fidelity.
FLUX.1 Krea [dev]
An opinionated text-to-image model from Black Forest Labs in collaboration with Krea that excels in photorealism. Creates images that avoid the oversaturated "AI look" with distinctive aesthetic approach.
Flux 1 Srpo
Cutting-edge 12-billion-parameter flow transformer for generating stunning, high-quality images from text with exceptional aesthetics. Perfect for both personal and commercial use.
Flux 2 Klein 9B Edit
High-quality 9B-parameter image editing model. Edit images using natural language prompts with up to 4 reference images for context-aware editing, style transfer, and element combination.
Why Use Flux AI
Text to Image
Generate photorealistic images from text prompts with exceptional accuracy. Flux handles complex compositions, accurate anatomy, and detailed environments.
Image Editing
Flux Kontext and Flux 2 Klein 9B offer precise image editing through text instructions. Modify specific elements while preserving the rest of the image.
Up to 4K Resolution
Generate images at resolutions up to 4 megapixels. Multiple aspect ratios supported for any use case from social media to print.
6 Model Variants
Access Flux Dev, Schnell, Kontext, Krea, SRPO, and Klein 9B Edit from one platform. Each variant optimized for different workflows.
100% Cloud-Based
No GPU required, no Python setup, no local installation. ComfyUI Web runs Flux on cloud GPUs — works on any device.
trial-credit tier Available
Start generating images with no credit card. Free accounts receive credits that refresh regularly.
How to Use Flux AI on ComfyUI Web
Generate your first Flux image in under a minute.
Choose a Flux Variant
Flux Dev for high-quality generation, Schnell for speed, Kontext for editing, Krea for photorealism, or Klein 9B for advanced editing with multi-image reference.
Write Your Prompt
Describe the image in detail: subject, composition, lighting, style, and mood. Flux supports prompts up to 8,000 tokens for precise control.
Generate & Download
Click generate and receive your image in seconds. Adjust prompt or settings, then download in PNG format at full resolution.
What Is Flux AI?
Flux is a family of text-to-image models created by Black Forest Labs, the company founded by the original creators of Stable Diffusion. Since its debut in August 2024, Flux has become the dominant open-source image generation model, known for photorealism, typography accuracy, and prompt adherence.
The Flux architecture uses a latent flow matching transformer that replaces the traditional UNet diffusion approach. This enables faster sampling, better text rendering, and more coherent compositions — particularly for complex multi-subject scenes.
Flux Model Variants Explained
Flux Dev is the primary development model, optimized for high-quality image generation with LoRA fine-tuning support. It's the best starting point for most creative workflows.
Flux Schnell ('fast' in German) is distilled for speed, generating near-Dev-quality images in 2-4 inference steps instead of 20+. This makes it 3-5x faster with minimal quality loss — ideal for rapid iteration.
Flux Kontext is specialized for image editing through text instructions. Upload an existing image and describe the changes you want — Kontext modifies specific elements with pro-level precision while preserving the rest.
Flux Krea (collaboration with Krea AI) is tuned for photorealism, producing images that avoid the oversaturated 'AI look' with a distinctive, more natural aesthetic.
Flux 1 SRPO is a 12-billion parameter model focused on exceptional aesthetics — it produces stunning, high-quality images with particular strength in artistic compositions.
Flux 2 Klein 9B Edit is the latest variant with advanced multi-reference editing, supporting up to 10 input images for composition. It handles complex editing tasks including style transfer, object insertion, and scene modification.
Technical Specifications
Flux models range from 4B (Klein) to 32B (Flux 2 Pro) parameters. On ComfyUI Web, we offer optimized variants that balance quality and generation speed for cloud deployment.
Supported resolutions include 1K, 2K, and 4K output with multiple aspect ratios (1:1, 3:2, 2:3, 4:3, 3:4, 16:9, 9:16). The built-in typography model handles text-in-images with high accuracy — a historically weak point for other image generators.
All Flux variants on ComfyUI Web accept text prompts. Kontext and Klein 9B additionally accept image inputs for editing workflows. LoRA fine-tuning is supported through Kontext Dev.
Flux vs Midjourney, DALL-E, and Stable Diffusion
Flux consistently outperforms DALL-E 3 and Stable Diffusion XL in prompt adherence, anatomy accuracy, and text rendering. Compared to Midjourney v6, Flux offers comparable aesthetic quality with full transparency and no platform lock-in.
The key advantage of Flux on ComfyUI Web is accessibility: generate professional-quality images with platform credits, in your browser, with no subscription required. For local users, Flux weights are freely downloadable from Hugging Face.
Frequently Asked Questions
- Is Flux AI free to use?
- Yes. Flux models are open-source and free to run locally. On ComfyUI Web, you get trial credits to generate images. Paid plans start at $9/month.
- What is the difference between Flux Dev and Flux Schnell?
- Flux Dev produces the highest quality images with full LoRA support. Flux Schnell is 3-5x faster with minimal quality loss, generating images in 2-4 steps instead of 20+. Use Schnell for rapid iteration.
- Can Flux AI edit existing images?
- Yes. Flux Kontext and Flux 2 Klein 9B Edit accept image inputs for editing. Describe the changes in text and the model modifies specific elements while preserving the rest.
- What resolution does Flux support?
- Flux generates images up to 4 megapixels (approximately 4K). Multiple aspect ratios are supported including 1:1, 16:9, 9:16, 3:2, 4:3, and more.
- Does Flux AI render text in images accurately?
- Yes. Flux has a built-in typography model specifically designed for accurate text rendering in images — a common weakness in other AI image generators.
- Do I need a GPU to use Flux AI?
- Not on ComfyUI Web. Our cloud GPUs handle all inference. For local use, Flux Dev requires approximately 12-24GB VRAM depending on resolution.
- Is Flux better than Midjourney?
- Flux matches Midjourney v6 in aesthetic quality while offering full transparency, no platform lock-in, and free access. On ComfyUI Web, you can try Flux with platform credits to compare.
- What is Flux Kontext used for?
- Flux Kontext is specialized for image editing through text instructions. Upload an image, describe your edits, and Kontext modifies specific elements while preserving the rest — with LoRA fine-tuning support.