colors
Back to gallery

Robust Hibiscadelphus

#851d2a
Notes

Robust Hibiscadelphus (#851D2A) is a deep red with a jewel character. It carries the deep, saturated richness of a gemstone. Authoritative and slightly formal, it works well for type and heavy UI elements. Its HSL profile (353°, 64%, 32%) places it in the balanced band at a dark lightness. It works well as a headline, icon, or deep background in an otherwise light layout, pairing cleanly with cream, bone, and warm neutrals. For a confident two-color system, pair it with its complementary teal. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#851d2a
RGB
rgb(133, 29, 42)
HSL
hsl(353, 64%, 32%)
HWB
hwb(353 11% 48%)
OKLCH
oklch(40.9% 0.138 19.4)
P3
color(display-p3 0.4790 0.1503 0.1755)
HSV
hsv(353, 78%, 52%)
LAB
lab(29.50% 44.04 19.41)
LCH
lch(29.50% 48.13 23.79)
CMYK
cmyk(0%, 78%, 68%, 48%)

Etymology

Robust
adjective

From the Latin robustus, of oak — implying strength combined with substance. As a color modifier, robust describes saturation combined with body: a robust burgundy, a robust olive. Sits in the bold-and-warm corner alongside strong and solid, with the slightly textural implication of a color that has substance behind the pigment.

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.

#851d2a
Original
#3b372a
Protanopia
#554d27
Deuteranopia
#920023
Tritanopia
#343434
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).
AAAon White
9.52:1
The quick brown foxSample body text at normal size. The wcag minimum for body contrast is 4.5:1 (AA) or 7:1 (AAA).
Failon Black
2.21:1

Wide gamut

Display P3 representation

The CSS Color 4 wide-gamut form of this color. Both swatches render the same color on every display — the P3 form only diverges from sRGB when a designer pushes channels outside sRGB's reach.

sRGB hex
sRGB hex
##851D2A
Display P3
Display P3
color(display-p3 0.4790 0.1503 0.1755)
P3 has subtle headroomOKLCH chroma 0.138

Moderately saturated colors gain a small bump in P3 — the difference is usually visible side-by-side on wide-gamut hardware but won't change the character of the color.

Related Colors

Canvas