Convert hue, saturation and lightness into the red, green and blue channels a screen actually uses.
Most APIs that draw pixels — canvas, image libraries, LED strips — want three channel numbers, while the colour you settled on is probably written in HSL because that is the form you can reason about. This conversion sits between the two and is exact: nothing is lost going this direction.
f(n) = L − a · max(−1, min(k − 3, 9 − k, 1)) where k = (n + H/30) mod 12, a = S · min(L, 1 − L)
The specification gives the conversion as a single function evaluated at three offsets — 0, 8 and 4 — producing red, green and blue. The clamping inside is what folds the hue circle into the six segments the older textbook formulations spell out case by case.
A number that disagrees with its source is a defect, not a rounding preference.
What did you enter, what did the tool show, and what did you expect instead? If you have a source that disagrees with ours, a link to it is the most useful thing you can send.
Opens your mail app with the page and tool already filled in.
Convert red, green and blue channels into hue, saturation and lightness, the form that says what a colour actually is.
Turn hue, saturation and lightness into a hex code — useful when a colour was picked by feel and now has to go into a stylesheet or a design file.
Convert a hex colour to its red, green and blue channels, including the shorthand and alpha forms defined by the CSS specification.