colors
Back to gallery

Open Seth Lagoon

#09abd1
Notes

Open Seth Lagoon (#09ABD1) 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 (191°, 92%, 43%) 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
#09abd1
RGB
rgb(9, 171, 209)
HSL
hsl(191, 92%, 43%)
HWB
hwb(191 4% 18%)
OKLCH
oklch(68.7% 0.125 221.4)
P3
color(display-p3 0.3026 0.6605 0.8037)
HSV
hsv(191, 96%, 82%)
LAB
lab(64.79% -22.92 -29.50)
LCH
lch(64.79% 37.35 232.16)
CMYK
cmyk(96%, 18%, 0%, 18%)

Etymology

Open
adjective

Old English open, unobstructed — used as a color modifier since the eighteenth century for hues that read as airy or uncrowded. Open blue, open green: moderate saturation combined with optical spaciousness, the slight visual breath of a hue that doesn't crowd the surface it covers. Sits at the crisp-bucket center alongside clear.

Seth
modifier

Egyptian Set, god-of-storms-and-desert-chaos. As a color modifier, seth implies a desert-storm-and-chaos-god quality, the visual register of Egyptian-Seth-and-Ombos-temple hand-desert-storm-and-chaos-god Egyptian-Seth-and-Ombos-temple-and-Osirian-conflict seth-and-desert-storm-and-chaos-god surfaces under Egyptian-Seth-and-Ombos-temple-and-Osirian-conflict Western-Desert-and-storm-cloud red-desert-storm-light. Sits at the modifier-and-myth end of the grid, parallel to horus and ptah 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.

#09abd1
Original
#95a6d3
Protanopia
#7d96d1
Deuteranopia
#00b7b7
Tritanopia
#8b8b8b
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
2.71:1
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
7.76:1

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
##09ABD1
Display P3
Display P3
color(display-p3 0.3026 0.6605 0.8037)
P3 has subtle headroomOKLCH chroma 0.125

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