Tools / Color Converter / RGB → HSL
RGB to HSL Converter.
RGB to HSL re-expresses the three additive channels as a hue angle, a saturation percentage, and a lightness percentage. It's the conversion behind every 'lighten 10%' or 'desaturate' operation in a design system.
Not a recognizable RGB color.
HSL
All formats
The RGB → HSL formula
Normalize to 0-1. L = (max+min)/2. S = 0 if max==min else (max−min)/(1−|2L−1|). H = 60° × the offset of the max channel.
Worked example
Convert rgb(154, 42, 42):
- Normalize → (0.604, 0.165, 0.165)
- Max = 0.604 (red), Min = 0.165
- L = 38%, S = 57%
- Red is max → H ≈ 0° (red)
- Result: hsl(0, 57%, 38%)
Python
import colorsys
r,g,b = 154/255, 42/255, 42/255
h,l,s = colorsys.rgb_to_hls(r,g,b)
print(round(h*360), round(s*100), round(l*100)) # 0 57 38FAQ
Why is saturation defined with lightness in the denominator?
HSL keeps perceived vividness roughly constant across lightness, so the same S means 'equally saturated' whether the color is light or dark. That requires the 1−|2L−1| term.