colors
Back to gallery

Calm Unda Lagoon

#54d1e0
Notes

Calm Unda Lagoon (#54D1E0) 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 (186°, 69%, 60%) 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
#54d1e0
RGB
rgb(84, 209, 224)
HSL
hsl(186, 69%, 60%)
HWB
hwb(186 33% 12%)
OKLCH
oklch(79.7% 0.111 206.2)
P3
color(display-p3 0.4686 0.8091 0.8684)
HSV
hsv(186, 63%, 88%)
LAB
lab(77.79% -29.89 -17.70)
LCH
lch(77.79% 34.74 210.64)
CMYK
cmyk(63%, 7%, 0%, 12%)

Etymology

Calm
adjective

Latin calma, heat of the day — paradoxically drifted in Italian to mean stillness. Used as a color modifier since the seventeenth century for hues that read as untroubled. Calm blue, calm gray: moderate saturation combined with optical quiet. Sits at the crisp-bucket near quiet and steady.

Unda
modifier

Latin unda, wave-or-water. As a color modifier, unda implies a Latin-wave-and-water-and-Roman-aqueduct quality, the visual register of Roman-aqueduct-and-Pontine-marsh-unda hand-Latin-wave-and-water-and-Roman-aqueduct Roman-aqueduct-and-Pontine-marsh-unda-and-Tiber-flow unda-and-Latin-wave-and-water surfaces under Roman-aqueduct-and-Pontine-marsh-unda-and-Tiber-flow Aqua-Claudia-and-Aqua-Marcia Roman-water-light. Sits at the modifier-and-Latin end of the grid, parallel to via and arbor in usage.

Lagoon
noun

A shallow body of saltwater partially or fully enclosed by a barrier — coral atoll lagoons in the Pacific, Venice's Laguna Veneta, the Florida Keys' backcountry. The color refers to the average reflectance of a calm tropical lagoon at midday: a saturated, slightly muted blue-green with the optical clarity of shallow water over white sand. Brighter than reef, cooler than aquamarine, with the postcard weight of a Pacific atoll seen from above.

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.

#54d1e0
Original
#c1c9e1
Protanopia
#acbae0
Deuteranopia
#00d9d5
Tritanopia
#b8b8b8
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
1.81:1
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
11.57:1

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
##54D1E0
Display P3
Display P3
color(display-p3 0.4686 0.8091 0.8684)
P3 has subtle headroomOKLCH chroma 0.111

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