colors
Back to gallery

Bold Hibiscadelphus

#b0371d
Notes

Bold Hibiscadelphus (#B0371D) is a true red with a vibrant character. It holds its own as a focal accent, carrying visual weight without tipping into neon territory. Its HSL profile (11°, 72%, 40%) places it in the balanced band at a mid lightness. It works across type, buttons, and borders, saturated enough to feel deliberate but balanced enough to not fight the rest of the palette. For a confident two-color system, pair it with its complementary cyan. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#b0371d
RGB
rgb(176, 55, 29)
HSL
hsl(11, 72%, 40%)
HWB
hwb(11 11% 31%)
OKLCH
oklch(51.2% 0.162 33.7)
HSV
hsv(11, 84%, 69%)
LAB
lab(41.30% 47.88 42.24)
LCH
lch(41.30% 63.85 41.42)
CMYK
cmyk(0%, 69%, 84%, 31%)

Etymology

Bold
adjective

Old English beald, brave, courageous — a quality word that crossed over to color in the late seventeenth century. Bold describes a color that asserts itself: high saturation combined with mid lightness, where the hue presents itself without compromise. Sits at the center of the bold-bucket grid, near strong and rich. Closer to a presence word than a pigment word.

Hibiscadelphus
noun

A genus of Hawaiian endemic hibiscus relatives — H. distans and H. giffardianus — whose deep red flowers are pollinated by Hawaiian honeycreepers. Most species are now extinct or critically endangered. The color refers to the petal of a fresh H. distans bloom: a saturated, slightly cool deep red with the satin finish of mallow-family flower.

Closest matches

The nearest named color in three reference sources, ranked by perceptual distance (ΔE76 in CIELAB). ΔE < 1 is imperceptible to most viewers; ΔE > 10 is clearly different. When two sources point to the same hex they’re merged into one tile; click any to open that color’s page.

Variations

Click any swatch to explore

Harmonies

Accessibility

Color-vision simulation

How this color appears to viewers with the four major color-vision-deficiency types. Computed via the Machado (2009) physiologically-based model. If a tile matches the original, the color reads the same to that viewer.

#b0371d
Original
#5b5018
Protanopia
#796b17
Deuteranopia
#c20b32
Tritanopia
#4f4f4f
Achromatopsia
WCAG contrast

The color used as foreground text against pure white and pure black, with the contrast ratio and WCAG 2.1 grade. Aim for AA (4.5:1) for body text and AA Large (3:1) for 18 pt+ headlines; AAA (7:1) is the gold standard for long-form reading surfaces.

The quick brown foxSample body text at normal size. The wcag minimum for body contrast is 4.5:1 (AA) or 7:1 (AAA).
AAon White
6.16:1
The quick brown foxSample body text at normal size. The wcag minimum for body contrast is 4.5:1 (AA) or 7:1 (AAA).
AA Largeon Black
3.41:1

Related Colors

Canvas