Colour
#A31728
- #A31728
- Red
- Dark
- Nearest: Brown
#A31728 is a red with RGB values 163, 23, 40 and HSL 353°, 75%, 36%. It is a dark colour, so white text on it reaches 7.7:1 contrast (AAA for normal text). The nearest named colour is Brown.
Colour values
#A31728#A31728
HEX#A31728
RGBrgb(163, 23, 40)
RGB (0–1)0.6392, 0.0902, 0.1569
RGB percentages63.9%, 9%, 15.7%
HSLhsl(352.7, 75.3%, 36.5%)
HSV / HSBhsv(352.7, 85.9%, 63.9%)
CMYK0%, 85.9%, 75.5%, 36.1%≈naive device-independent conversion; real print needs an ICC profile
24-bit integer10,688,296
CSS custom property--colour: #A31728;
Brightness & contrast
Relative luminance0.08553WCAG 2.x, 0 is black and 1 is white
Perceived brightness91.9 of 255ITU-R BT.601 weighting
Light or darkDark
Best text colour on this backgroundWhitecontrast 7.75:1
Contrast with white7.75:1WCAG normal text: AAA
Contrast with black2.71:1WCAG normal text: Fail
Greyscale equivalent#363636
Inverted#5CE8D7
Colour vision & accessibility
Distinguishable without hueShifts in lightness toonever rely on hue alone to carry meaning
Contrast with white, large text7.75:1WCAG large text: AAA
Contrast with black, large text2.71:1WCAG large text: Fail
Named colours
Hue familyred
CSS keyword usableNo exact keyword
Colour harmonies
Complementary#17A392
Analogous#A3176E, #A34C17
Triadic#28A317, #1728A3
Split complementary#17A34C, #176EA3
Tetradic#6EA317, #17A392, #4C17A3
Tints, shades & saturation
Channel breakdown
R163
G23
B40
Red163 (63.9%)
Green23 (9%)
Blue40 (15.7%)
Hue352.71°
Saturation (HSL)75.27%
Lightness36.47%
Dominant channelRed
Hex per channelR A3 · G 17 · B 28
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