colors
Back to gallery

Frank Atoll

#175f36
Notes

Frank Atoll (#175F36) is a deep teal with a jewel character. It carries the deep, saturated richness of a gemstone. Authoritative and slightly formal, it works well for type and heavy UI elements. Its HSL profile (146°, 61%, 23%) places it in the balanced band at a dark lightness. It works well as a headline, icon, or deep background in an otherwise light layout, pairing cleanly with cream, bone, and warm neutrals. For a confident two-color system, pair it with its complementary magenta. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#175f36
RGB
rgb(23, 95, 54)
HSL
hsl(146, 61%, 23%)
HWB
hwb(146 9% 63%)
OKLCH
oklch(43.1% 0.097 153.7)
P3
color(display-p3 0.1805 0.3670 0.2266)
HSV
hsv(146, 76%, 37%)
LAB
lab(35.27% -32.25 17.32)
LCH
lch(35.27% 36.61 151.77)
CMYK
cmyk(76%, 0%, 43%, 63%)

Etymology

Frank
adjective

From the Old French franc, free, sincere — used as a color modifier since the seventeenth century for hues that read as direct and unhedged. Frank red, frank brown: moderate-to-high saturation combined with optical directness. Sits at the crisp-bucket alongside direct and honest.

Atoll
noun

A ring-shaped coral reef enclosing a central lagoon — the geological signature of subsiding volcanic islands ringed by upward-growing coral. Atoll color refers to the unifying blue-green of a Maldivian-style atoll lagoon seen from above: a saturated, slightly cool deep blue-green with the optical clarity of shallow tropical water.

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.

#175f36
Original
#5f5733
Protanopia
#565039
Deuteranopia
#005e55
Tritanopia
#4d4d4d
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).
AAAon White
7.70:1
The quick brown foxSample body text at normal size. The wcag minimum for body contrast is 4.5:1 (AA) or 7:1 (AAA).
Failon Black
2.73:1

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
##175F36
Display P3
Display P3
color(display-p3 0.1805 0.3670 0.2266)
P3 has subtle headroomOKLCH chroma 0.097

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