Releasing weights for FLUX.1 Krea

217 vmatsiiako 79 7/31/2025, 1:41:45 PM krea.ai ↗

Comments (79)

vunderba · 41m ago
Nice release. Ran some preliminary tests using the 12b Txt2Img Krea model. Its biggest wins seems to be raw speed (and possibly realism) but perhaps unsurprisingly did not score any higher on the leaderboard for prompt adherence than the normal Flux.1D model.

https://genai-showdown.specr.net

On another note, there seem to be some indication that Wan 2.2+ future models might end up becoming significant players in the T2I space though you'll probably need a metric ton of LoRAs to cover some of the lack of image diversity.

dvrp · 8m ago
Can you point to a URL with the tests you’ve done?

Also, FWIW, this model focus was around aesthetics rather than strict prompt adherence. Not to excuse the bad samples, but to emphasize what was one of the research goals.

It’s a thorny trade-off, but an important one if one wants to get rid of what’s sometimes known as “the flux look”.

Re: Wan 2.2 I’ve also been reading of people commenting about using Wan 2.2 for base generation and Krea for the refiner pass which I thought was interesting.

dvrp · 14h ago
Hello everyone.

I’m the Co-founder and CTO of Krea. We’re excited because we wanted to release the weights for our model and share it with the HN community for a long time.

My team and I will try to be online and try to answer any questions you may have throughout the day.

mk_stjames · 5h ago
Any plans to get into working with the Flux 'Kontext' version, the editing models? I think the use cases of such prompted image editing is just wildly huge. Their demo blew my mind, although I haven't seen the quality of the open weight version yet. It is also a 12B distill.
jackphilson · 5h ago
Hi. Thanks for this. What is your goal of doing so? From a business standpoint. Or is it purely altruistic?
dvrp · 5h ago
Haha-classic!

It’s simple: hackability and recruiting!

The open-source community hacking around it and playing with it PLUS talented engineers who may be interested in working with us already makes this release worth it. A single talented distributed systems engineer has a lot of impact here.

Also, the company ethos is around AI hackability/controllability, high-bar for talent, and AI for creatives - so this aligns perfectly.

The fact that Krea serves both in-house and 3rd-Party models tells you that we are not that bullish on models being a moat.

wjrb · 5h ago
I can say that it's definitely working on me! I hadn't heard of Krea before, and this is a great introduction to your work. Thanks for sharing it.
cchance · 5h ago
People underestimate how much goodwill companies gain from pushing opensource stuff out, not just from word of mouth but even picking up users for their commercial offerings too, while i could run opensource and appreciate it in a lot of cases using API's from the companies that i like (mostly ones that do opensource stuff) tends to be easier for bigger stuff...
yieldcrv · 4h ago
(unless the code repository and history is embarrassingly bad, which is most repositories)
sangwulee · 13h ago
Hi! I'm lead researcher on Krea-1. FLUX.1 Krea is a 12B rectified flow model distilled from Krea-1, designed to be compatible with FLUX architecture. Happy to answer any technical questions :)
oompty · 5h ago
The model looks incredible!

Regarding this part: > Since flux-dev-raw is a guidance distilled model, we devise a custom loss to finetune the model directly on a classifier-free guided distribution.

Could you go more into detail on the specific loss used for this and any other possible tips for finetuning this that you might have? I remember the general open source ai art community had a hard time with finetuning the original distilled flux-dev so I'm very curious about that.

swyx · 6h ago
thanks for doing this!

what does " designed to be compatible with FLUX architecture" mean and why is that important?

sangwulee · 6h ago
FLUX.1 is one of the most popular open weights text-to-image models. We distilled Krea-1 to FLUX.1 [dev] model so that the community can adopt it seamlessly into existing ecosystem. Any finetuning code, workflows, etc that was built on top of FLUX.1 [dev] can be reused with our model :)
swyx · 5h ago
do LoRAs conflict with your distillation?
sangwulee · 4h ago
The architecture is the same so we found that some LoRAs work out-of-the box, but some LoRAs don't. In those cases, I would expect people to re-run their LoRA finetuning with the trainer they've used.
vipermu · 7h ago
hey hn! I'm one of the founders at Krea.

we prepared a blogpost about how we trained FLUX Krea if you're interested in learning more: https://www.krea.ai/blog/flux-krea-open-source-release

orphea · 4h ago
Off topic but did you really hide scroll bars on the website? Why...?

  .scrollbar-hide {
    -ms-overflow-style: none;
    scrollbar-width: none;
  }
VladVladikoff · 1h ago
UI brought to you by vibe code
BoorishBears · 43m ago
nah, Krea is just from that side of design twitter where you don't uppercase letters and you can break the rules sometimes. very atypography-coded.
ilc · 6h ago
Tried a simple prompt, and got some pretty interesting results:

"Octopus DJ spinning the turntables at a rave."

The human like hands the DJ sprouts are interesting, and no amount of prompting seems to stop them.

Opinionated, as the paper says.

earthicus · 5h ago
Describing it as "Octopus DJ with no fingers" got rid of the hands for me, but interestingly, also removed every anthropomorphized element of the octopus, so that it was literally just an octopus spinning turntables.
ilc · 4h ago
I still get octopus hands, even with just "Octopus DJ with no fingers." nothing else.

Maybe you got a lucky roll :)

bluehark · 6h ago
Do you have an NVIDIA optimized version? Similar to how RTX accelerated FLUX.1 Kontext: https://blogs.nvidia.com/blog/rtx-ai-garage-flux-kontext-nim...
sangwulee · 6h ago
We have not added a separate RTX accelerated version for FLUX.1 Krea, but the model is fully compatible with existing FLUX.1 dev codebase. I don't think we made a separate onnx export for it though. Doing 4~8 bit quantized version with SVDQuant would be a nice follow up so that the checkpoint is more friendly for consumer grade hardware.
SubiculumCode · 3h ago
I've never gotten one to make what I am thinking of: A Galton board. At the top, several inches apart are two holes from which balls drop. One drops blue balls, the other red balls. They form a merged distribution below in columns, demonstrating dual overlapping normal distributions

Imagine one of these: https://imgur.com/a/DiAOTzJ but with two spouts at the top dropping different colored balls

Its attempts: https://imgur.com/undefined https://imgur.com/a/uecXDzI

CGMthrowaway · 3h ago
Have you tried building one irl? I can't find a video of a double one
bangaladore · 7h ago
Can someone ELI5 why the safetensor file is 23.8 GB, given the 12B parameter model? Does the model use closer to 24 GB of VRAM or 12 GB of VRAM. I've always associated a 1 billion parameter = 1 GB of VRAM. Is this estimate inaccurate?
sangwulee · 7h ago
Quick napkin math assuming bfloat16 format : 1B * 16 bits = 16B bits = 2GB. Since it's a 12B parameter model, you get around ~24GB. Downcasting to bfloat16 from float32 comes with pretty minimal performance degradation, so we uploaded the weights in bfloat16 format.
petercooper · 7h ago
That's a good ballpark for something quantized to 8 bits per parameter. But you can 2x/4x that for 16 and 32 bit.
7734128 · 7h ago
I've never seen a 32 bit model. There's bound to be a few of them, but it's hardly a normal precision.
zamadatix · 6h ago
Some of the most famous models were distributed as F32, e.g. GPT-2. As things have shifted more towards mass consumption of model weights it's become less and less common to see.
nodja · 5h ago
> As things have shifted more towards mass consumption of model weights it's become less and less common to see.

Not the real reason. The real reason is that training has moved to FP/BF16 over the years as NVIDIA made that more efficient in their hardware, the same reason you're starting to see some models being released in 8bit formats (deepseek).

Of course people can always quantize the weights to smaller sizes, but the master versions of the weights is usually 16bit.

petercooper · 5h ago
And on the topic of image generation models, I think all the Stable Diffusion 1.x models were distributed in f32.
piperswe · 7h ago
A parameter can be any size float. Lots of downloadable models are FP8 (8 bits per parameter), but it appears this model is FP16 (16 bits per parameter)

Often, the training is done in FP16 then quantized down to FP8 or FP4 for distribution.

dragonwriter · 2h ago
I think they are bfloat16, not FP16, but they are both 16bpw formats, so it doesn't make a size difference.
TuringNYC · 6h ago
I usually use https://github.com/axolotl-ai-cloud/axolotl on Lambda/Together for working with these types of models. Curious what others are using? What is the quickest way to get started? They mention Pre-training and Post-training but sadly didnt provide any reference starter scripts.
dvrp · 6h ago
We actually have a GitHub repository to help with inference code.

Check this out: https://github.com/krea-ai/flux-krea

Let me see if we can add more details on the blog post and thanks for the flag!

TuringNYC · 6h ago
Thanks! Yes, the inference is pretty straightforward, but the real opportunity IMHO is the custom pre-training and post-training opportunities given the open weights.
kmavm · 7h ago
Amazing. I can practically smell that owl it looks so darned owl-like.

From the article it doesn’t seem as though photorealism per se was a goal in training; was that just emergent from human preferences, or did it take some specific dataset construction mojo?

sangwulee · 7h ago
I love owls. Photorealism was one of the focus areas for training because "AI look" (e.g. plastic skin) was biggest complaint for FLUX.1 model series. Photorealism was achieved with both careful curation of finetuning and preference dataset.
TuringNYC · 6h ago
I'd recommend you offer a clearly documented pathway for companies to license commercial output usage rights if they get the results they seek (i'll know soon enough!)
dvrp · 6h ago
You can find details about the license here: https://huggingface.co/black-forest-labs/FLUX.1-dev/blob/mai...

In a nutshell, it follows the same license as BFL Flux-dev model.

dvrp · 7h ago
OsrsNeedsf2P · 7h ago
Cool to see an open weight model for this. But what's the business use case? Is it for people who want to put fake faces on their website that don't look AI generated?
dvrp · 7h ago
Thanks!

From a business point of view, there are many use-cases. Here's a list in no particular order:

- You can quickly generate assets that can be used _alongside_ more traditional tools such as Adobe Photoshop, After Effects, or Maya/Blender/3ds Max. I've seen people creating diffuse maps for 3D using a mix of diffusion models and manual tweaking with Photoshop.

- Because this model is compatible with the FLUX architecture, we've also seen people personalizing the model to keep products or characters consistent across shots. This is useful in e-commerce and fashion industry. We allow easy training in our website — we labeled it Krea 1 — to do this, but the idea with this release is to encourage people with local rigs and more powerful GPUs to be able to tweak with LoRAs themselves too.

- Then I've seen fascinating use-cases such as UI/UX designers who prompt the model to create icons, illustrations, and sometimes even whole layouts that then they use as a reference (like Pinterest) to refine their designs on Figma. This reminds me of people who have a raster image and then vectorize it manually using the pen tool in Adobe Illustrator.

We also have seen big companies using it for both internal presentations and external ads across marketing teams and big agencies like Publicis.

EDIT: Then there's a more speculative use-case that I have in mind: Generating realistic pictures of food.

While many restaurants have people who either make illustrations of their menu items and others have photographers, the big tail of restaurants do not have the means/expertise to do this. The idea we have from the company perspective is to make it as easy as snapping a few pictures of all your dishes and being able to turn all your menu (in this case) into a set of professional-looking pictures that accurately represent your menu.

artninja1988 · 6h ago
Thanks for the release to the team! Any plans on doing the same for FLUX.1 Kontext?
jacooper · 5h ago
Non-commercial license... What's the point even, I can't use it for anything.
hhh · 5h ago
for the love of the game, not for corporate greed
lawlessone · 4h ago
How did you train while ensuring only images consensually acquired were used?
whimsicalism · 4h ago
Likely the same way visual artists ensure that they only learn from images with permissive licenses.
bluehark · 6h ago
How large was the dataset used for post-training?
sangwulee · 6h ago
We used two types of datasets for post-training. Supervised finetuning data and preference data used for RLHF stage. You can actually use less than < 1M samples to significantly boost the aesthetics. Quality matters A LOT. Quantity helps with generalisation and stability of the checkpoints though.
lawlessone · 4h ago
How is the data collected?
sangwulee · 3h ago
The highest quality finetuning data was hand curated internally. I would say our post training pipeline is quite similar to SeedDream 2.0 ~ 3.0 series from ByteDance. Similar to them, we use extensive quality filters and internal models to get the highest quality possible. Even from there, we still hand curate a hand-picked subset.

No comments yet

gshklovski · 7h ago
Helpful blog post for understanding what kind of data is needed for these models!

Does this have any application for generating realistic scenes for robotics training?

sangwulee · 7h ago
Thank you! Glad you find it helpful. The model is focused on photorealism so it should be able to generate most realistic scenes. Although, I think using 3D engines would be more suitable for typical cases for robotics training since it gives you ground truth data on objects, location, etc.

One interesting use case would be if you are focusing on a robotics task that would require perception of realistic scenes.

dvrp · 7h ago
Hey thanks! I’ll ask Sangwu to hop here to answer this and give a more research-oriented answer
erwannmillon · 7h ago
yeah data really is everything that was the number one lesson from this whole project
erwannmillon · 7h ago
yoo i'm also a researcher on the krea 1 project and happy to answer any questions :)
gutianpei · 4h ago
hello Erwann, great work! I have a very technical question just for you: how are you today?
paparicio · 6h ago
Great, these people are crazy. CONGRATS!!!
dvrp · 6h ago
Haha thanks! Do you happen to have a use-case for it?
qlm · 6h ago
Images still look AI generated
dvrp · 6h ago
Yeah, there are still imperfections. But, it’s surprising to us how much the quality can be improved without the need of a whole pre-training (re-) run.
Lerc · 4h ago
Is it possible (or do people already do this), to train a classifier to identify the AI look and use it as an adversary to try and maximise both 'quality' and 'not that sort of quality'?
sangwulee · 4h ago
I actually tried a few experiments in early exploration stages! I trained a small classifier to judge AI vs non-AI images. Use it as a reward model to do small RL / post training experiments. Sadly, was not too successful. We found that directly finetuning the model on high quality photorealistic image was most reliable.

Another note about preference optimisation and RL is that it has really high quality ceiling but needs to be very carefully tuned. It's easy to get perfect anatomy and structure if you decide to completely "collapse" the model. For instance, ChatGPT images are collapsed to have slight yellow color palette. FLUX images always have this glossy, plastic texture with overly blurry background. It's similar to reward hacking behavior you see in LLMs where they sound overly nice and chatty.

I had to make a few compromises to balance between "stable, collapsed, boring model" and "unstable, diverse, explorative" model.

Lerc · 2h ago
I could see how you might need a multi channel classifier so that one exists on a range (A) of -1 = "This looks like AI" to 1="This does not look like AI" and another(R) where 1="The above factor is relevant to this image" to 0="The AI-ness of this image is not a meaningful concept

Then optimise for max (Quality + A*R)

Arguably amplitude of A should do R but I think the AI-ness and the AI-ness-relevance are distinct concepts (It could be highly relevant but it can't tell what it should be).

sergiotapia · 6h ago
For the Krea team that might be reading: I was trying to evaluate Krea for my image gen use case, and couldn't find:

- cost per image - latency per image

Hope you guys can add it somewhere!

dvrp · 6h ago
Yup... We have the following: https://www.krea.ai/pricing

Though we wanted to keep this technical blogpost free from marketing fluff, but maybe we over-did it.

However, sometimes it's hard to give an exact price per image, as it depends on resolution, number of steps, whether a LoRA is being used or not, etc.

leftstrokeviral · 6h ago
How much data is the model trained on?
dvrp · 6h ago
Copying and pasting Sangwu’s answer:

We used two types of datasets for post-training. Supervised finetuning data and preference data used for RLHF stage. You can actually use less than < 1M samples to significantly boost the aesthetics. Quality matters A LOT. Quantity helps with generalisation and stability of the checkpoints though.

lawlessone · 3h ago
How is data acquired and curated?
CaptainFever · 3h ago
Nitpick: this is not open weights, this is weights available. The license restricts many things like commercial, NSFW, etc.
dang · 17m ago
Alright we've made the title not say open, in the hope of routing around this objection.
dragonwriter · 2h ago
I mean this started with Stable Diffusion 1.x->XL which were only loosely open, and has just gotten worse with progressively farther from open licensed image gen models being described as “open weights”, but, yes, Flux.1 Krea (like the weights-available versions of Flux.1 from BFL itself) is not open even to the degree of the older versions of Stable Diffusion; weights available and “free-as-in-beer licensed for certain uses”, sure, but not open.
dvrp · 13h ago
For Dang or HN-mods:

I noticed that the URL for this submission is wrong: I tried to submit the correct URL (https://www.krea.ai/blog/flux-krea-open-source-release) but, for some reason, the submission gets flagged as duplicated and then I can only find this item which has a URL to our old blog post.

In the mean time, I'll setup a server-side redirect from the old blog post to our new one, but it would be nice to fix the link and I don't think I can do it on my side.

dang · 8h ago
It's because https://www.krea.ai/blog/flux-krea-open-source-release contains this:

  <link rel="canonical" href="https://www.krea.ai/blog/new-krea">
Our software follows canonical links when it finds them.

I've fixed the link above now (and rolled back the clock on the submission, to make up for lost time) but you might want to fix this for future pages.

dvrp · 7h ago
OMG. Thank you! I had to setup a CDN-level redirect and I was so confused as to why when I asked others to help, their submissions were flagged as [dupe] or [dead]

Thank you so much! I knew that HN software was advanced, but I didn’t know you guys used Canonical URLs like Google does. Smart and thanks for helping us with this slip!!!

dang · 15m ago
Oh you're welcome - it does lead to a lot of not-obvious problems like this but I think it's worth it overall. It helps with duplicate detection, merging threads, and so on.