colors
Back to gallery

Functional Horn Lagoon

#57d1f1
Notes

Functional Horn Lagoon (#57D1F1) is a true cyan with a neon character. It sits at the high-saturation edge of its family. Use it sparingly, as signage, accent, or highlight against darker surfaces. Its HSL profile (192°, 85%, 64%) 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
#57d1f1
RGB
rgb(87, 209, 241)
HSL
hsl(192, 85%, 64%)
HWB
hwb(192 34% 5%)
OKLCH
oklch(80.4% 0.116 218.2)
P3
color(display-p3 0.4750 0.8092 0.9303)
HSV
hsv(192, 64%, 95%)
LAB
lab(78.45% -24.45 -25.81)
LCH
lch(78.45% 35.55 226.55)
CMYK
cmyk(64%, 13%, 0%, 5%)

Etymology

Functional
adjective

Latin fūnctiō, performance — adjectival suffix -al. As a color modifier, functional implies a clear-and-purpose-fit-and-utilitarian quality, the crisp color of Mid-Century-Modern and Bauhaus form-follows-function design-aesthetic. Sits at the crisp-and-functional end of the grid, parallel to practical and utilitarian in usage.

Horn
modifier

Old English horn, horn. As a color modifier, horn implies a translucent-keratin quality, the visual register of cattle-horn-and-deer-antler hand-shaped-and-polished translucent-keratin button-and-comb-and-knife-handle horn-and-antler surfaces under translucent-horn-and-antler hand-polished light. Sits at the modifier-and-texture end of the grid, parallel to bone and pith 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.

#57d1f1
Original
#bccbf3
Protanopia
#a6bbf1
Deuteranopia
#00dcdb
Tritanopia
#b9b9b9
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
1.78:1
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
11.80:1

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
##57D1F1
Display P3
Display P3
color(display-p3 0.4750 0.8092 0.9303)
P3 has subtle headroomOKLCH chroma 0.116

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