Harmonious colours from one choice
Colour schemes that work tend to follow relationships on the colour wheel. Give this tool a base colour and it builds the classic sets — complementary, analogous, triadic and tetradic — by rotating the hue, so you can see several coherent directions at a glance.
A starting point, generated locally
These schemes are a strong foundation to refine rather than a finished palette, and every swatch copies with a click. It all runs on your device with nothing uploaded.