colors
Back to gallery

Grounded Cerulean

#428ad6
Notes

Grounded Cerulean (#428AD6) is a true azure 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 (211°, 64%, 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 orange. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#428ad6
RGB
rgb(66, 138, 214)
HSL
hsl(211, 64%, 55%)
HWB
hwb(211 26% 16%)
OKLCH
oklch(62.3% 0.136 252.0)
HSV
hsv(211, 69%, 84%)
LAB
lab(56.28% 2.15 -45.53)
LCH
lch(56.28% 45.58 272.70)
CMYK
cmyk(69%, 36%, 0%, 16%)

Etymology

Grounded
adjective

Old English grund, bottom / foundation — past-participle of ground. As a color modifier, grounded implies a saturated-and-foundational quality where the hue anchors the surrounding palette through its weighty presence. Sits at the bold-and-balanced end of the grid, parallel to centered and anchored.

Cerulean
noun

From the Latin caeruleum, originally referring to dark blue paint pigment of the Roman world, then via French céruléen into English. As a modern art-supply name, cerulean blue is the cobalt-tin oxide pigment introduced in 1805. The color refers to a clean, slightly green-shifted blue with the matte finish of mineral pigment in linseed oil: lighter than cobalt, deeper than aqua, with the painter's weight of a word for sky.

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.

#428ad6
Original
#688fd9
Protanopia
#5381d4
Deuteranopia
#009ca6
Tritanopia
#808080
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
3.60:1
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
5.84:1

Related Colors

Canvas