colors
Back to gallery

Effective Pourpre

#903b57
Notes

Effective Pourpre (#903B57) is a true red with an earthy character. It leans grounded and natural, the kind of color that plays well with wood, clay, linen, and warm neutrals. Its HSL profile (340°, 42%, 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 teal. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#903b57
RGB
rgb(144, 59, 87)
HSL
hsl(340, 42%, 40%)
HWB
hwb(340 23% 44%)
OKLCH
oklch(47.6% 0.118 2.1)
P3
color(display-p3 0.5242 0.2517 0.3401)
HSV
hsv(340, 59%, 56%)
LAB
lab(37.38% 38.81 1.45)
LCH
lch(37.38% 38.84 2.15)
CMYK
cmyk(0%, 59%, 40%, 44%)

Etymology

Effective
adjective

Latin effectīvus, productive — adjectival suffix -ive. As a color modifier, effective implies a clear-and-purpose-achieving quality where the hue carries the visual register of successful-task-completion design-element. Sits at the crisp-and-functional end of the grid, parallel to practical and useful in usage.

Pourpre
noun

French for purple in its classical sense — the deep red-purple of Tyrian dye and the pourpre cardinalice of medieval French ecclesiastical dress. The color refers to a pourpre-dyed French silk: a saturated, slightly cool deep red-purple with the satin finish of plant-and-shell dye. The French cousin of porpora.

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.

#903b57
Original
#4a4e58
Protanopia
#615e55
Deuteranopia
#9b3346
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).
AAAon White
7.12:1
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
2.95:1

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
##903B57
Display P3
Display P3
color(display-p3 0.5242 0.2517 0.3401)
P3 has subtle headroomOKLCH chroma 0.118

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