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Imperial Altair Ruby

#a91c2b
Notes

Imperial Altair Ruby (#A91C2B) is a true red with a warm character. It leans warm, pulling light toward red, orange, and yellow. Naturally inviting, it suits editorial and hospitality contexts. Its HSL profile (354°, 72%, 39%) 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
#a91c2b
RGB
rgb(169, 28, 43)
HSL
hsl(354, 72%, 39%)
HWB
hwb(354 11% 34%)
OKLCH
oklch(47.7% 0.174 22.3)
HSV
hsv(354, 83%, 66%)
LAB
lab(36.82% 55.21 29.35)
LCH
lch(36.82% 62.53 27.99)
CMYK
cmyk(0%, 83%, 75%, 34%)

Etymology

Imperial
adjective

From the Latin imperialis, of the empire — applied to color since the medieval period for the hues reserved for sovereigns and empires: imperial purple of Tyrian dye, imperial yellow of Ming-dynasty porcelain. As a modifier, imperial implies saturation combined with the institutional weight of a color owned by a court. Sits in the bold-and-deep corner, alongside royal.

Altair
modifier

Arabic al-nasr-al-tā'ir, the-flying-eagle. As a color modifier, altair implies a fast-spinning-and-summer-triangle quality, the visual register of Aquila-Eagle-and-Summer-Triangle-Altair hand-fast-spinning-and-summer-triangle Aquila-Eagle-and-Summer-Triangle-and-Bortle-1-sky altair-and-fast-spinning-and-summer-triangle surfaces under Aquila-Eagle-and-Summer-Triangle-and-Bortle-1-sky July-and-August-summer-vista white-stellar-light. Sits at the modifier-and-cosmic end of the grid, parallel to vega and deneb in usage.

Ruby
noun

From the Latin ruber — simply, red. The gemstone is a chromium-tinged corundum, harder than anything in nature except diamond, and so saturated that a fine Burmese pigeon's blood ruby at auction outpaces a comparable diamond by weight. The color borrows the gem's confidence: a clear, glassy red without the brown of garnet or the blue of crimson.

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.

#a91c2b
Original
#4a432a
Protanopia
#6c6126
Deuteranopia
#ba0024
Tritanopia
#3b3b3b
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
7.27:1
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
2.89:1

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