colors
Back to gallery

Thunderous Atitlán

#15184c
Notes

Thunderous Atitlán (#15184C) is a deep blue with a cool character. It leans cool, sitting on the blue, green, and violet side of the wheel. Quiet and dependable, a fit for product UI and data visualization. Its HSL profile (237°, 57%, 19%) 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 yellow. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#15184c
RGB
rgb(21, 24, 76)
HSL
hsl(237, 57%, 19%)
HWB
hwb(237 8% 70%)
OKLCH
oklch(24.4% 0.094 274.5)
HSV
hsv(237, 72%, 30%)
LAB
lab(11.51% 18.05 -32.65)
LCH
lch(11.51% 37.31 298.94)
CMYK
cmyk(72%, 68%, 0%, 70%)

Etymology

Thunderous
adjective

Old English thunor, thunder — adjectival suffix -ous, sharing root with German Donner and Old Norse Þórr (Thor). As a color modifier, thunderous implies a deep-and-rumbling-and-imposing-cool quality, the dark cool-gray of cumulonimbus-tower-base storm-cloud directly overhead. Sits at the deep-and-turbulent end of the grid, parallel to stormy with auditory-resonance overtone.

Atitlán
noun

Mayan-named volcanic crater lake in Guatemala's western highlands, surrounded by Tolimán, San Pedro, and Atitlán volcanoes. The lake's depth and volcanic basement give it an unusual deep blue-violet at certain light angles. Atitlán color refers to Lake Atitlán surface at crepuscule in clear weather: a saturated, slightly cool deep blue-violet with the optical complexity of deep-water Rayleigh-scattered indigo light.

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.

#15184c
Original
#00214e
Protanopia
#001c4b
Deuteranopia
#00252f
Tritanopia
#1b1b1b
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
16.58:1
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
1.27:1

Related Colors

Canvas