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Cool Morningglory

#63a8b8
Notes

Cool Morningglory (#63A8B8) 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 (191°, 37%, 55%) 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
#63a8b8
RGB
rgb(99, 168, 184)
HSL
hsl(191, 37%, 55%)
HWB
hwb(191 39% 28%)
OKLCH
oklch(69.2% 0.073 214.3)
P3
color(display-p3 0.4518 0.6521 0.7131)
HSV
hsv(191, 46%, 72%)
LAB
lab(65.05% -17.49 -15.02)
LCH
lch(65.05% 23.05 220.66)
CMYK
cmyk(46%, 9%, 0%, 28%)

Etymology

Cool
adjective

Old English cōl, of low temperature — used as a color modifier as the complement to warm. Cool gray, cool blue: the optical impression of a slight blue-green shift, even within otherwise warm or neutral hues. Sits across the crisp, hushed, pale, and neutral buckets.

Morningglory
noun

The family Convolvulaceae — particularly Ipomoea purpurea, the climbing annual whose blue-purple morning-blooming trumpet flowers close by midday. The color refers to a fresh Ipomoea flower in early morning: a saturated, slightly cool deep blue-violet with the satin finish of single-day trumpet bloom.

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.

#63a8b8
Original
#9ca4b9
Protanopia
#8f9ab8
Deuteranopia
#39aead
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
2.68:1
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
7.82:1

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
##63A8B8
Display P3
Display P3
color(display-p3 0.4518 0.6521 0.7131)
Inside sRGBOKLCH chroma 0.073

This color sits well within the sRGB cube. P3 and sRGB share the gray axis and most desaturated tones, so a P3 display renders this identically to an sRGB display.

Related Colors

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