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Praetorian Surkh

#b31f06
Notes

Praetorian Surkh (#B31F06) 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 (9°, 94%, 36%) 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
#b31f06
RGB
rgb(179, 31, 6)
HSL
hsl(9, 94%, 36%)
HWB
hwb(9 2% 30%)
OKLCH
oklch(49.5% 0.185 31.6)
P3
color(display-p3 0.6447 0.1836 0.1021)
HSV
hsv(9, 97%, 70%)
LAB
lab(38.86% 56.46 49.99)
LCH
lch(38.86% 75.41 41.52)
CMYK
cmyk(0%, 83%, 97%, 30%)

Etymology

Praetorian
adjective

Latin praetōriānus, of the praetor — adjectival suffix, referring to the Roman-Imperial elite guard-cohorts. As a color modifier, praetorian implies a saturated-and-elite-and-imperial-guard quality, the deep-rich color of Roman-Praetorian-Guard elite-imperial-bodyguard scarlet-tunic-and-bronze-armor military-formation. Sits at the bold-and-formal end of the grid, parallel to spartan and imperial.

Surkh
noun

The Persian word for red in its most saturated, formal sense — used in Iranian poetry and miniature painting for the ribbons of court banners, the robes of warriors, and the high-saturation reds of Safavid tile. The color refers to a surkh-dyed Persian carpet: a saturated, slightly cool deep red with the matte finish of plant-dye-on-wool. Deeper than crimson, warmer than burgundy.

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.

#b31f06
Original
#514700
Protanopia
#756700
Deuteranopia
#c6001d
Tritanopia
#3d3d3d
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).
AAon White
6.74:1
The quick brown foxSample body text at normal size. The wcag minimum for body contrast is 4.5:1 (AA) or 7:1 (AAA).
AA Largeon Black
3.12:1

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
##B31F06
Display P3
Display P3
color(display-p3 0.6447 0.1836 0.1021)
P3 has visible headroomOKLCH chroma 0.185

This color is chromatic enough that authoring it as P3 native (instead of clamping to sRGB) gives a perceptibly more saturated render on wide-gamut displays — modern Macs, iPhones, iPads, and most recent OLED laptops.

Related Colors

Canvas