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Pure Celtic Crimson

#a7201b
Notes

Pure Celtic Crimson (#A7201B) is a true 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 (2°, 72%, 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 cyan. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#a7201b
RGB
rgb(167, 32, 27)
HSL
hsl(2, 72%, 38%)
HWB
hwb(2 11% 35%)
OKLCH
oklch(47.4% 0.171 28.2)
P3
color(display-p3 0.6016 0.1785 0.1411)
HSV
hsv(2, 84%, 65%)
LAB
lab(36.61% 53.00 38.29)
LCH
lch(36.61% 65.39 35.84)
CMYK
cmyk(0%, 81%, 84%, 35%)

Etymology

Pure
adjective

Latin purus, clean, unmixed — applied to color since antiquity for hues that contain only one pigment without dilution by white, black, or another color. Pure red is the textbook ideal: high saturation, mid lightness, no shift. Sits at the bold-bucket center, parallel to true and strong.

Celtic
modifier

Latin Celticus, of-the-Celts. As a color modifier, celtic implies a knotwork-and-La-Tène quality, the visual register of Irish-and-Welsh-and-Scottish Celtic-knotwork hand-carved bronze-and-stone metalwork-and-illuminated-manuscript surfaces under Celtic-Irish-Welsh-Scottish illuminated-manuscript-tradition light. Sits at the modifier-and-cultural end of the grid, parallel to norse and welsh in usage.

Crimson
noun

From the Old Spanish cremesin, itself from the Arabic qirmiz — the kermes scale insect, dried and ground into a brilliant carmine dye prized in the medieval Mediterranean. For centuries the most expensive red on a draper's shelf, reserved for cardinals, kings, and the cloth that gave English the word crimson. Cooler than scarlet, deeper than rose; the color of pomegranate seeds and a serious occasion.

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.

#a7201b
Original
#4c4318
Protanopia
#6d6113
Deuteranopia
#b80021
Tritanopia
#3c3c3c
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
7.33:1
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
2.87:1

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
##A7201B
Display P3
Display P3
color(display-p3 0.6016 0.1785 0.1411)
P3 has subtle headroomOKLCH chroma 0.171

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.

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