colors
Back to gallery

True Cycle Cerulean

#0c5f75
Notes

True Cycle Cerulean (#0C5F75) is a deep cyan 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 (193°, 81%, 25%) places it in the highly saturated band at a dark 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
#0c5f75
RGB
rgb(12, 95, 117)
HSL
hsl(193, 81%, 25%)
HWB
hwb(193 5% 54%)
OKLCH
oklch(45.1% 0.080 221.8)
HSV
hsv(193, 90%, 46%)
LAB
lab(37.01% -14.50 -18.92)
LCH
lch(37.01% 23.84 232.53)
CMYK
cmyk(90%, 19%, 0%, 54%)

Etymology

True
adjective

Old English trēowe, faithful — used as a color modifier since the seventeenth century for hues that read as the canonical version of their family. True red, true blue: the saturation is full, the hue is neither shifted nor adulterated. Sits at the center of the bold and crisp buckets, marking the unequivocal middle of any chromatic family.

Cycle
modifier

Greek kýklos, circle / cycle. As a color modifier, cycle implies a repeating-and-circular-time quality, the visual register of seasonal-and-lunar-and-astronomical repeating-and-cyclic period-marker celestial-and-natural cycle-and-rhythm surfaces under repeating cyclic-and-seasonal light. Sits at the modifier-and-time end of the grid, parallel to phase and year in usage.

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.

#0c5f75
Original
#525c76
Protanopia
#455375
Deuteranopia
#006666
Tritanopia
#4f4f4f
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
7.22:1
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
2.91:1

Related Colors

Canvas