How to Generate Fast Images with Flux.1 Schnell in ComfyUI

Flux.1 Schnell is the distilled, speed-focused sibling of Flux Dev. It is tuned to produce a good image in roughly 4 steps instead of 20-plus, and it ships under the permissive Apache 2.0 license. If you want fast drafts or you are on a weaker GPU, Schnell is the model to reach for.

What you need

• A recent ComfyUI install
• The same CLIP and VAE files used for Flux Dev (clip_l, t5xxl, ae)
• An 8 GB GPU works well; the fp8 build runs on less
• About 24 GB of free disk space

Step 1: Download the Schnell model file

Download flux1-schnell.safetensors and place it in models/unet. Schnell shares the text encoders and VAE with Dev, so if you already set up Flux Dev you only need this one new file.

Step 2: Reuse the Flux loaders

Open your Flux workflow and switch the UNET loader from flux1-dev to flux1-schnell. Leave the DualCLIPLoader and VAE loader exactly as they were. Nothing else about the model wiring changes.

Step 3: Dial the sampler down to 4 steps

This is the key difference from Dev. Schnell is distilled for very few steps and does not use real CFG, so set steps to 4 and CFG to 1. Use the euler sampler with the simple scheduler. Higher step counts waste time without improving the image.

Step 4: Queue and compare

Enter a prompt and click Queue Prompt. On a mid-range card the image lands in a few seconds. Run the same prompt a couple of times with different seeds to find a composition you like, then refine the wording.

Result: near-instant Flux renders for ideation. When a draft looks promising, you can rerun the same prompt and seed through Flux Dev at higher steps for a more polished final.