Color & design
Color utilities for designers and developers.
What it is for
Colour is one of the few design decisions that affects aesthetics and whether people can actually read what you wrote at the same time. Choosing well is not a matter of taste: there are mathematical relationships explaining why certain colours work together, and measurable thresholds determining whether text is legible.
On top of that sits a practical problem that appears the moment you use more than one tool: the same colour is written differently depending on where it goes. HEX on the web, RGB in editors, CMYK at the printer, HSL when you want to adjust a tone by hand. Translating between them manually is slow and error-prone.
This section covers the three usual needs: converting between formats, finding combinations that work, and checking the result meets accessibility minimums before publishing.
Which tool do I need
- I have a colour and need it in another format
- The colour converter translates instantly between HEX, RGB, HSL and CMYK.
- I do not know which colours to use
- The palette generator proposes five harmonious colours spaced around the colour wheel. Press a few times until a combination fits.
- I want to know whether my text reads well
- The contrast checker calculates the ratio between text and background and tells you whether it meets WCAG levels AA and AAA.
- I need the colours from an image or a logo
- Extract image colours, in the image section, analyses the file and returns the dominant tones.
- I want a lighter version of my brand colour
- Use the converter, switch the colour to HSL and raise the lightness while keeping the hue. Far more precise than guessing in RGB.
Frequently asked questions
What minimum contrast do I need?
For normal text, 4.5:1 meets level AA, which is what is usually required and what accessibility legislation mandates for many public-sector sites. Level AAA asks for 7:1.
Why do my colours look different when printed?
Screens work in RGB with light and paper in CMYK with ink. Some colours, particularly heavily saturated greens and blues, simply cannot be reproduced in print.
Does a harmonious palette guarantee legibility?
No. Harmony and contrast are different things: two colours can work beautifully together and still be illegible one on the other. Always check contrast separately.