colors
Back to gallery

Assured Arbor Rose

#900a37
Notes

Assured Arbor Rose (#900A37) is a deep 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 (340°, 87%, 30%) 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 teal. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#900a37
RGB
rgb(144, 10, 55)
HSL
hsl(340, 87%, 30%)
HWB
hwb(340 4% 44%)
OKLCH
oklch(42.1% 0.162 11.0)
P3
color(display-p3 0.5168 0.1132 0.2203)
HSV
hsv(340, 93%, 56%)
LAB
lab(30.46% 52.66 12.49)
LCH
lch(30.46% 54.12 13.34)
CMYK
cmyk(0%, 93%, 62%, 44%)

Etymology

Assured
adjective

Old French aseürer, to give assurance — past-participle of assure. As a color modifier, assured implies a saturated-and-confident quality where the hue carries unwavering certainty about its own visual identity. Sits at the bold-and-confident end of the grid, parallel to certain and poised.

Arbor
modifier

Latin arbor, tree-or-trunk. As a color modifier, arbor implies a Latin-tree-and-vine-arbor quality, the visual register of Pliny-Natural-History-and-Roman-villa-arbor hand-Latin-tree-and-vine-arbor Pliny-Natural-History-and-Roman-villa-arbor-and-pergola arbor-and-Latin-tree-and-vine-arbor surfaces under Pliny-Natural-History-and-Roman-villa-arbor-and-pergola Pompeii-and-Tuscan-pergola-and-grape-arbor leafy-shade-light. Sits at the modifier-and-Latin end of the grid, parallel to via and domus in usage.

Rose
noun

The Latin rosa, the Greek rhodon, the Persian gul — every European language has a different name for the same flower and the same color. Rose covers the spectrum from blush to fuchsia depending on the cultivar, but in pigment shorthand it means a cool, slightly bluish red — the inside of a damask petal, the dye that washes out of madder root.

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.

#900a37
Original
#373738
Protanopia
#575134
Deuteranopia
#9e0021
Tritanopia
#2a2a2a
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
9.19:1
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
2.28:1

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
##900A37
Display P3
Display P3
color(display-p3 0.5168 0.1132 0.2203)
P3 has subtle headroomOKLCH chroma 0.162

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