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Strong Ruby

#9f151d
Notes

Strong Ruby (#9F151D) 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 (357°, 77%, 35%) 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
#9f151d
RGB
rgb(159, 21, 29)
HSL
hsl(357, 77%, 35%)
HWB
hwb(357 8% 38%)
OKLCH
oklch(45.2% 0.170 25.4)
HSV
hsv(357, 87%, 62%)
LAB
lab(33.98% 53.50 34.05)
LCH
lch(33.98% 63.42 32.47)
CMYK
cmyk(0%, 87%, 82%, 38%)

Etymology

Strong
adjective

Old English strang, firm, vigorous — applied to color since the sixteenth century. Strong red, strong tea: a color at full strength is the maximum saturation the medium can produce. Sits at the saturated mid corner of the grid, parallel to bold in usage but slightly more focused on pigment density than on assertion.

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

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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.

#9f151d
Original
#443d1b
Protanopia
#655a16
Deuteranopia
#b0001a
Tritanopia
#333333
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
8.08:1
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
2.60:1

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