colors
Back to gallery

Sure Alpine

#1bbcc5
Notes

Sure Alpine (#1BBCC5) 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 (183°, 76%, 44%) 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
#1bbcc5
RGB
rgb(27, 188, 197)
HSL
hsl(183, 76%, 44%)
HWB
hwb(183 11% 23%)
OKLCH
oklch(72.5% 0.120 201.1)
P3
color(display-p3 0.3463 0.7264 0.7642)
HSV
hsv(183, 86%, 77%)
LAB
lab(69.63% -34.40 -15.48)
LCH
lch(69.63% 37.73 204.23)
CMYK
cmyk(86%, 5%, 0%, 23%)

Etymology

Sure
adjective

Old French seur, certain — used as a color modifier since the medieval period for hues that read as confident and stable. Sure red, sure blue: moderate saturation combined with optical commitment. Sits at the crisp-bucket center alongside steady and true.

Alpine
noun

Of the Alps, the European mountain range — and the saturated blue of Alpine lake water (Lake Geneva, Lake Como, Lake Brienz) fed by glacier-melt. Alpine color refers to Lake Brienz at midday: a saturated, slightly cool deep blue with the optical clarity of glacier-fed alpine lake water.

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.

#1bbcc5
Original
#adb3c6
Protanopia
#97a3c6
Deuteranopia
#00c4be
Tritanopia
#9a9a9a
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
2.32:1
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
9.05:1

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
##1BBCC5
Display P3
Display P3
color(display-p3 0.3463 0.7264 0.7642)
P3 has subtle headroomOKLCH chroma 0.120

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