Show HN: Generate random gradients like on OpenAI's website

31 venkii 9 8/14/2025, 4:16:40 AM gradients.venki.dev ↗

Comments (9)

venkii · 1d ago
Hey HN!

Check out this fun tool I built to make cover images for my blog. The main goal: interesting looking random gradients, that all draw from a single color palette.

I stumbled upon this post from Justin Jay Wang [1], who designed for OpenAI - describing methods for random gradients, including the one that shipped on OpenAI’s homepage from 2020-2022.

Since the post included ~10 SVGs, I was able to reverse engineer the SVG parameters, and decided to put up a generator. You can see the exact deets in my Github README [2].

I also use it to generate cover images for my Substack [3] - if you want to see what using a bunch of images generated by it looks like.

[1] https://justinjay.wang/methods-for-random-gradients/

[2] https://github.com/venkr/gradient-gen

[3] https://venkii.substack.com/

tomaspollak · 1d ago
Great work! Maybe you can add an option to use the 'heightmap' method described by Justin in his blog post. And maybe let users add their own palettes? :)
venkii · 1d ago
Thanks! I'll look into adding custom palettes & the heightmap method. Might not get to it tbh - but I'll take a look.
beeman · 1d ago
Looks awesome! It would be good to add a license to your repo!
venkii · 1d ago
Done - thanks :)
soocil5 · 13h ago
I think Noise will make it better.
NoelJacob · 1d ago
This is great but I wish CSS output was generated. Anything that can do that?
venkii · 1d ago
Mmm interesting.

I'm not sure if it's possible in pure CSS, maybe it is? It relies on creating new SVG elements.

I think including the SVG in whatever website would usually be the simplest way to use it and it's super lightweight.

Feel free to take a look at the SVG generation function here [1] and lmk if you have any ideas to make it happen in pure CSS.

[1] https://github.com/venkr/gradient-gen/blob/main/src/EllipseG...

Stevemiller07 · 1d ago
Nice work. Gradients can add a dynamic feel without distracting users, and OpenAI’s subtle animated style is a good example. A generator like this makes it easy to experiment with color palettes and get consistent, visually pleasing results quickly.