colors
Back to gallery

Heavy Madder

#e91d0a
Notes

Heavy Madder (#E91D0A) is a true red with a neon character. It sits at the high-saturation edge of its family. Use it sparingly, as signage, accent, or highlight against darker surfaces. Its HSL profile (5°, 92%, 48%) places it in the highly saturated band at a mid lightness. Best used in small doses, like logos, CTAs, focus rings, or highlight text, where its saturation becomes a feature rather than noise. 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
#e91d0a
RGB
rgb(233, 29, 10)
HSL
hsl(5, 92%, 48%)
HWB
hwb(5 4% 9%)
OKLCH
oklch(59.5% 0.233 30.1)
P3
color(display-p3 0.8392 0.2178 0.1409)
HSV
hsv(5, 96%, 91%)
LAB
lab(49.77% 71.79 60.54)
LCH
lch(49.77% 93.91 40.14)
CMYK
cmyk(0%, 88%, 96%, 9%)

Etymology

Heavy
adjective

Old English hefig, weighty — cognate with heave. Used as a color modifier since at least the seventeenth century to indicate weight in saturation as much as value: heavy with pigment, heavy-bodied. In the engine's adjective grid, heavy sits alongside deep and plush in the dark-and-saturated quadrant. Closer to a fabric description than a pure value word.

Madder
noun

Rubia tinctorum, the dyer's madder — the root pigment that fed European red textile production from antiquity until synthetic alizarin replaced it in 1869. Less brilliant than kermes, more lightfast than safflower, madder-dyed wool was the workhorse red of Persian carpets, British redcoats, and Turkish kilim. The color carries that history: a warm, slightly orange red with the matte finish of cloth rather than glaze.

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.

#e91d0a
Original
#675a00
Protanopia
#978600
Deuteranopia
#ff001e
Tritanopia
#474747
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
4.52:1
The quick brown foxSample body text at normal size. The wcag minimum for body contrast is 4.5:1 (AA) or 7:1 (AAA).
AAon Black
4.64:1

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
##E91D0A
Display P3
Display P3
color(display-p3 0.8392 0.2178 0.1409)
P3 has visible headroomOKLCH chroma 0.233

This color is chromatic enough that authoring it as P3 native (instead of clamping to sRGB) gives a perceptibly more saturated render on wide-gamut displays — modern Macs, iPhones, iPads, and most recent OLED laptops.

Related Colors

Canvas