Color Name API
Name any colour. The nearest endpoint takes a colour as a hex, an rgb() value, an r,g,b triple or another name and returns the closest of the 140+ CSS named colours — matched perceptually with CIE76 Lab distance, not naive RGB, so the name actually looks right — along with the distance and whether it is an exact match. The name endpoint resolves a CSS colour keyword (e.g. rebeccapurple, cornflowerblue) to its hex and RGB, and list returns the whole named-colour set. Perfect for design tools and pickers, accessibility and theming, turning brand hex codes into human labels, and naming colours in generated palettes. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 4 endpoints. Distinct from colour conversion / palette / contrast tooling, which does not name colours.
api.oanor.com/colorname-api