Flux.2 Klein + Refiner — Clean, Fast, No Nonsense
I'll be honest: I was almost ready to give up on Flux.2 Klein.
I spent an entire night downloading and testing workflows I found online — some popular, some less so — and none of them worked the way I needed. Generation times were absurd, sometimes hitting 400 seconds or more. On top of that, I kept getting images at resolutions I never asked for, with no upscale nodes in sight and no clear explanation. I was going crazy trying to fix issues I didn't even fully understand.
At some point I thought: maybe this is just how Flux.2 Klein works. But something didn't feel right. So instead of giving up, I built my own workflow from scratch — adapting it to the way I actually work.
Turns out the answer was simpler than I expected.
What this workflow does
This is a clean, straightforward Flux.2 Klein workflow with an optional SDXL refiner pass. No bloated node chains, no mystery outputs, no hidden upscaling. What you set is what you get.
Generation times I've achieved:
Without refiner: 20–30 seconds per generation
With refiner (SDXL 1.0 DMD): 35–40 seconds
(obviously based on my hardware, so your results may vary)
Resolution: fully customizable via a dedicated node — I personally use 1536×1920, but you can set whatever you need.
How the refiner works
After Flux.2 Klein generates the base image, a second KSampler with an SDXL 1.0 DMD checkpoint refines it at low denoise. Nothing exotic — just a classic refiner setup that adds detail and polish without rebuilding the image from scratch. You can run it or skip it depending on your needs.
Why am I sharing this?
Because I wasted hours on workflows that looked impressive but performed terribly, and I don't want the same to happen to you. This one works (at least for me :)... ). It's not fancy, but it's fast, predictable, and the results speak for themselves.
If you try it, let me know what you think. And if you use it for portraits or lifestyle shots, I'd love to see what you create.
All sample images were generated with this workflow. No post-processing.
Description
Version 2.0 — What changed
This update fixes a wiring mistake I made in the final stage of the Refiner that was causing the generation to stop, and adds two RAM cleanup nodes that can help free up memory between generations — useful if you're running into slowdowns or VRAM issues after multiple runs, especially if your hardware is near its limits. If that's not a concern for you, just bypass those nodes and ignore them.
Known issue — help appreciated
There's a bug I haven't been able to track down yet: when using the final Save Image with Metadata node, CivitAI incorrectly displays the positive prompt in the negative prompt field as well.
I'm aware of it and will be looking into it over the coming weeks. In the meantime, if anyone more experienced spots the cause and wants to let me know in the comments, I'd be genuinely grateful — and happy to push a fix as soon as I understand the problem.