colors
Back to gallery

Heavy Knell Cobalt

#104383
Notes

Heavy Knell Cobalt (#104383) is a deep azure 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 (213°, 78%, 29%) 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 orange. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#104383
RGB
rgb(16, 67, 131)
HSL
hsl(213, 78%, 29%)
HWB
hwb(213 6% 49%)
OKLCH
oklch(38.9% 0.120 256.6)
P3
color(display-p3 0.1244 0.2587 0.4965)
HSV
hsv(213, 88%, 51%)
LAB
lab(28.80% 9.40 -40.55)
LCH
lch(28.80% 41.62 283.05)
CMYK
cmyk(88%, 49%, 0%, 49%)

Etymology

Heavy
adjective

Old English hefig, weighty — cognate with heave. Used as a color modifier since at least the seventeenth century to indicate weight in saturation as much as value: heavy with pigment, heavy-bodied. In the engine's adjective grid, heavy sits alongside deep and plush in the dark-and-saturated quadrant. Closer to a fabric description than a pure value word.

Knell
modifier

Old English cnyll, funeral-bell. As a color modifier, knell implies a funeral-and-passing-bell quality, the visual register of English-funeral-and-passing-bell slow-and-tolling-funeral mourning-bell-and-bell-tower-tolling slow-and-mourning surfaces under slow-tolling-funeral-bell mourning candlelight. Sits at the modifier-and-time end of the grid, parallel to bell and vesper in usage.

Cobalt
noun

Element Co, atomic number 27 — German Kobold, goblin, named by miners who found the metal interfered with smelting silver ore. Cobalt blue is the cobalt-aluminate pigment introduced by Louis Jacques Thénard in 1802: a saturated, slightly green-shifted deep blue with the matte finish of mineral pigment in oil. Cooler than ultramarine, warmer than prussian, with the painter's weight of a pigment used by Renoir, Van Gogh, and Cézanne.

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.

#104383
Original
#1f4985
Protanopia
#003f82
Deuteranopia
#00525c
Tritanopia
#3d3d3d
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
9.76:1
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
2.15:1

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
##104383
Display P3
Display P3
color(display-p3 0.1244 0.2587 0.4965)
P3 has subtle headroomOKLCH chroma 0.120

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