colors
Back to gallery

Smoky Rex

#640c66
Notes

Smoky Rex (#640C66) is a deep violet 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 (299°, 79%, 22%) places it in the highly saturated band at a dark 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 green. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#640c66
RGB
rgb(100, 12, 102)
HSL
hsl(299, 79%, 22%)
HWB
hwb(299 5% 60%)
OKLCH
oklch(36.1% 0.155 327.2)
P3
color(display-p3 0.3583 0.0845 0.3862)
HSV
hsv(299, 88%, 40%)
LAB
lab(23.45% 47.12 -30.26)
LCH
lch(23.45% 56.00 327.29)
CMYK
cmyk(2%, 88%, 0%, 60%)

Etymology

Smoky
adjective

An adjectival form of smoke, used as a color word since at least the fourteenth century. Smoky implies a slightly muted, slightly hazed quality — as if the color were seen through a layer of suspended particulate. Used across both deep and neutral buckets: a smoky black has slightly less density than pure black; a smoky gray has slightly less coolness than pure gray.

Rex
noun

Latin rex, king — adopted into English as the technical term for imperial purple-and-gold regalia. The rex color tradition refers to the Tyrian purple imperial robes of Roman emperors after Diocletian's 295 CE vestiarium reforms. Rex color refers to an imperial Roman purpura-dyed paludamentum cloak: a saturated, slightly cool deep violet with the matte finish of multi-bath Tyrian shellfish-dye on Roman imperial wool.

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.

#640c66
Original
#003168
Protanopia
#263c64
Deuteranopia
#671e3b
Tritanopia
#252525
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
11.76:1
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
1.79:1

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
##640C66
Display P3
Display P3
color(display-p3 0.3583 0.0845 0.3862)
P3 has subtle headroomOKLCH chroma 0.155

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