colors
Back to gallery

Effective Purpurnyy

#643a88
Notes

Effective Purpurnyy (#643A88) is a true indigo 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 (272°, 40%, 38%) 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 lime. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#643a88
RGB
rgb(100, 58, 136)
HSL
hsl(272, 40%, 38%)
HWB
hwb(272 23% 47%)
OKLCH
oklch(43.6% 0.129 306.7)
P3
color(display-p3 0.3692 0.2352 0.5163)
HSV
hsv(272, 57%, 53%)
LAB
lab(32.95% 34.23 -36.67)
LCH
lch(32.95% 50.16 313.03)
CMYK
cmyk(26%, 57%, 0%, 47%)

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.

Purpurnyy
noun

Russian пурпурный, purple — derived from Latin purpura via Greek porphyra. The Russian Orthodox liturgical color for Pentecost and the deep-purple-and-gold iconostasis tradition. Purpurnyy color refers to a Russian Orthodox cathedral iconostasis royal-doors panel: a saturated, slightly cool deep violet with the matte finish of egg-tempera ultramarine-and-cinnabar on gilt gesso. Slightly cooler than Spanish púrpura.

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.

#643a88
Original
#1f4c8b
Protanopia
#2e4e86
Deuteranopia
#5e495b
Tritanopia
#494949
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
8.39:1
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
2.50:1

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
##643A88
Display P3
Display P3
color(display-p3 0.3692 0.2352 0.5163)
P3 has subtle headroomOKLCH chroma 0.129

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