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Useful Cane Turquoise

#21bad1
Notes

Useful Cane Turquoise (#21BAD1) is a true cyan with a vibrant character. It holds its own as a focal accent, carrying visual weight without tipping into neon territory. Its HSL profile (188°, 73%, 47%) places it in the balanced band at a mid lightness. It works across type, buttons, and borders, saturated enough to feel deliberate but balanced enough to not fight the rest of the palette. 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
#21bad1
RGB
rgb(33, 186, 209)
HSL
hsl(188, 73%, 47%)
HWB
hwb(188 13% 18%)
OKLCH
oklch(72.6% 0.121 211.0)
P3
color(display-p3 0.3487 0.7188 0.8073)
HSV
hsv(188, 84%, 82%)
LAB
lab(69.50% -29.27 -22.25)
LCH
lch(69.50% 36.77 217.24)
CMYK
cmyk(84%, 11%, 0%, 18%)

Etymology

Useful
adjective

Latin ūsus, use — adjectival suffix -ful. As a color modifier, useful implies a clear-and-purpose-serving quality where the hue carries the visual register of helpful-and-supporting design-element. Sits at the crisp-and-functional end of the grid, parallel to practical and serviceable in usage.

Cane
modifier

Old French canne, reed / cane. As a color modifier, cane implies a hand-cut-bamboo-or-rattan quality, the visual register of English-and-Edwardian-and-Asian-cane hand-cut-and-woven-cane bamboo-and-rattan-and-wicker hand-cut-cane-and-rattan surfaces under English-and-Edwardian-and-Asian hand-cut-cane-and-rattan furniture-and-craft light. Sits at the modifier-and-texture end of the grid, parallel to bark and hemp in usage.

Turquoise
noun

The hydrated copper-aluminum phosphate mined in Persia and the American Southwest for thousands of years — the firuze of Iran, the chalchihuitl of Mesoamerica, the heart of Pueblo and Navajo silverwork. The color refers to a fine Sleeping Beauty turquoise from Arizona: a saturated, slightly green-shifted blue with the slight matrix of host-rock veining. Brighter than persian, lighter than cerulean.

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.

#21bad1
Original
#a7b3d2
Protanopia
#91a3d1
Deuteranopia
#00c4c1
Tritanopia
#9b9b9b
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
2.33:1
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
9.01:1

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
##21BAD1
Display P3
Display P3
color(display-p3 0.3487 0.7188 0.8073)
P3 has subtle headroomOKLCH chroma 0.121

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