colors
Back to gallery

Fortified Rust

#aa3c07
Notes

Fortified Rust (#AA3C07) is a true orange 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 (20°, 92%, 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 azure. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#aa3c07
RGB
rgb(170, 60, 7)
HSL
hsl(20, 92%, 35%)
HWB
hwb(20 3% 33%)
OKLCH
oklch(50.7% 0.154 40.3)
HSV
hsv(20, 96%, 67%)
LAB
lab(40.89% 43.16 49.95)
LCH
lch(40.89% 66.01 49.18)
CMYK
cmyk(0%, 65%, 96%, 33%)

Etymology

Fortified
adjective

Latin fortificāre, to make strong — past-participle of fortify. As a color modifier, fortified implies a saturated-and-strengthened-and-defensive quality, the deep-rich color of Vauban-style military-fortification stone-and-earth rampart-and-bastion architecture. Sits at the bold-and-fortified end of the grid, parallel to bastioned and armored.

Rust
noun

Iron oxide — Fe₂O₃ — the slow union of iron with oxygen, accelerated by water and salt. The color is not the bright orange of fresh rust but the deeper, drier brown-red that forms after weeks of weather: the surface of an abandoned car, a Cor-Ten steel sculpture, the desert-varnished sandstone of the American Southwest. Earthier than copper, warmer than maroon.

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.

#aa3c07
Original
#5d5100
Protanopia
#776a00
Deuteranopia
#bc1b34
Tritanopia
#505050
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
6.25:1
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
3.36:1

Related Colors

Canvas