colors
Back to gallery

Luminous Cardoon

#21e4af
Notes

Luminous Cardoon (#21E4AF) is a true teal with a vibrant character. It holds its own as a focal accent, carrying visual weight without tipping into neon territory. Its HSL profile (164°, 78%, 51%) 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 red. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#21e4af
RGB
rgb(33, 228, 175)
HSL
hsl(164, 78%, 51%)
HWB
hwb(164 13% 11%)
OKLCH
oklch(81.8% 0.161 167.8)
HSV
hsv(164, 86%, 89%)
LAB
lab(81.24% -57.01 13.33)
LCH
lch(81.24% 58.55 166.84)
CMYK
cmyk(86%, 0%, 23%, 11%)

Etymology

Luminous
adjective

Latin lūminōsus, full of light — adjectival suffix -ous, derived from lūmen (light). As a color modifier, luminous implies a saturated-and-light-emitting quality where the hue carries internal-glow visual register. Sits at the bright-and-saturated end of the grid, parallel to radiant and resplendent in usage.

Cardoon
noun

Cynara cardunculus, the Mediterranean thistle — relative of the globe artichoke (C. cardunculus var. scolymus) — with deeply lobed silver-green foliage and architectural form. The color refers to mature cardoon foliage in a kitchen garden: a soft, slightly cool silver-green-blue with the matte finish of large pinnately lobed leaves.

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.

#21e4af
Original
#ded3ac
Protanopia
#c8c3b3
Deuteranopia
#00e5d5
Tritanopia
#b7b7b7
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).
Failon White
1.64:1
The quick brown foxSample body text at normal size. The wcag minimum for body contrast is 4.5:1 (AA) or 7:1 (AAA).
AAAon Black
12.78:1

Related Colors

Canvas