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Sterile Cycladic

#2181a6
Notes

Sterile Cycladic (#2181A6) is a true cyan with a cool character. It leans cool, sitting on the blue, green, and violet side of the wheel. Quiet and dependable, a fit for product UI and data visualization. Its HSL profile (197°, 67%, 39%) 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 orange. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#2181a6
RGB
rgb(33, 129, 166)
HSL
hsl(197, 67%, 39%)
HWB
hwb(197 13% 35%)
OKLCH
oklch(56.7% 0.102 229.3)
P3
color(display-p3 0.2515 0.4986 0.6369)
HSV
hsv(197, 80%, 65%)
LAB
lab(50.42% -13.97 -27.37)
LCH
lch(50.42% 30.73 242.95)
CMYK
cmyk(80%, 22%, 0%, 35%)

Etymology

Sterile
adjective

Latin sterilis, barren / not-fertile — sharing root with Greek steiros (barren). As a color modifier, sterile implies a clear-and-medical-clean-and-stripped quality, the crisp color of operating-theater surgical-environment white-and-stainless-steel surfaces. Sits at the crisp-and-clean end of the grid, parallel to sanitary and hygienic in usage.

Cycladic
noun

Of the Cyclades, the Greek archipelago — and the saturated blue of Cycladic-island cupolas, painted blue-and-white church domes, and the deep Mediterranean water of Mykonos, Santorini, Naxos. Cycladic color refers to a Cycladic church dome against the sea: a saturated, slightly cool deep blue with the matte finish of limewash-and-cobalt paint.

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.

#2181a6
Original
#6e7fa8
Protanopia
#5c73a5
Deuteranopia
#008b8d
Tritanopia
#6f6f6f
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).
AA Largeon White
4.42:1
The quick brown foxSample body text at normal size. The wcag minimum for body contrast is 4.5:1 (AA) or 7:1 (AAA).
AAon Black
4.76:1

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
##2181A6
Display P3
Display P3
color(display-p3 0.2515 0.4986 0.6369)
P3 has subtle headroomOKLCH chroma 0.102

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.

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