A small, sharp color lab
HueKit brings together the color and CSS jobs that interrupt real work, into one clean toolkit that is fast, free and private.
What HueKit is
HueKit is a collection of focused color and CSS tools. It converts colors between hex, RGB, HSL, HSV and CMYK, generates box shadows, gradients and glassmorphism, checks WCAG contrast, and extracts palettes from images. There is also a library of 254 named colors, each with its own reference page.
Why it runs in your browser
Every tool here is fully client side. That is a deliberate choice with real benefits. Results appear the instant you type, because there is no server round trip. Your colors and images never leave your device, so there is nothing to upload and nothing to leak. And once a page has loaded, the tools keep working even with no connection.
No accounts, work stays on your device
HueKit has no sign up and asks for nothing about you. The colors you type and the images you drop in are processed in your browser and are never uploaded. HueKit may show ads to cover its costs, and those partners can set their own cookies. How that works, and the consent choices offered to EEA and UK visitors, are covered in the privacy policy.
Who builds it
HueKit is built and maintained by FusionStudios, a Dutch web studio that builds and runs a small family of free tools alongside its client work. HueKit is one of them, and the person behind the studio is Jamey Weber. There is no company behind HueKit as a separate entity, no investors and no growth target: it exists because these were the jobs that kept interrupting real work.
That matters for two reasons you can check rather than take on trust. There is no revenue that depends on you staying on the page, which is why the whole dataset is published as free JSON under a CC0 license and why every AI crawler is allowed by name in robots.txt. And there is a name attached to the color math, which is more than most converter sites offer. If a value here is wrong, there is somebody to tell: hello@huekit.co, or the contact form.
If you need a site or a tool like this built properly, that is what FusionStudios does for a living. No banner, no popup, just the link.
How the color math works
All conversions use standard, well understood formulas, and every one of them is written down with its source on the methodology page, including the places where the answer is an approximation. Contrast uses the WCAG relative luminance method, unchanged between WCAG 2.1 and 2.2, so pass and fail results match what an auditor would expect. CMYK uses the naive mapping, which is right for on screen previews and wrong as a press handover.
The conversion functions live in a single file with a test script that round-trips twenty sample colors through every color space and checks the anchor values the specifications fix. The OKLCH implementation reproduces Tailwind CSS's own published hex values from its published OKLCH ones, which is an outside check rather than a claim about our own code.
Start here
The most popular starting point is the hex to RGB converter. From there, the full color converter opens up every model and builds harmonies, and the contrast checker keeps your text readable. Browse everything from the home page, or take the whole library as data.
Last updated by FusionStudios. Every value on this page is computed by the same functions the tools use. How this is calculated.