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Effective Helix Verdigris

#28b4b8
Notes

Effective Helix Verdigris (#28B4B8) is a true cyan 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 (182°, 64%, 44%) places it in the balanced band at a mid lightness. It works across type, buttons, and borders, saturated enough to feel deliberate but balanced enough to not fight the rest of the palette. 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
#28b4b8
RGB
rgb(40, 180, 184)
HSL
hsl(182, 64%, 44%)
HWB
hwb(182 16% 28%)
OKLCH
oklch(70.2% 0.112 197.9)
P3
color(display-p3 0.3466 0.6958 0.7151)
HSV
hsv(182, 78%, 72%)
LAB
lab(66.94% -33.57 -12.36)
LCH
lch(66.94% 35.77 200.21)
CMYK
cmyk(78%, 2%, 0%, 28%)

Etymology

Effective
adjective

Latin effectīvus, productive — adjectival suffix -ive. As a color modifier, effective implies a clear-and-purpose-achieving quality where the hue carries the visual register of successful-task-completion design-element. Sits at the crisp-and-functional end of the grid, parallel to practical and useful in usage.

Helix
modifier

Greek ἕλιξ, spiral-or-coil. As a color modifier, helix implies a planetary-nebula-and-spiraling-coil quality, the visual register of Helix-Nebula-and-Eye-of-God hand-planetary-nebula-and-spiraling-coil Helix-Nebula-and-Eye-of-God-and-NGC-7293 helix-and-planetary-nebula-and-spiraling-coil surfaces under Helix-Nebula-and-Eye-of-God-and-NGC-7293 Aquarius-and-Hubble-deep-field planetary-nebula-light. Sits at the modifier-and-cosmic end of the grid, parallel to nebula and corona in usage.

Verdigris
noun

The basic copper carbonate that forms on weathered copper and bronze — the pigment scraped from oxidized metal and used in Renaissance painting before being supplanted by more stable greens. The color refers to a thick verdigris on aged copper roofing or the Statue of Liberty's surface: a soft, slightly muted blue-green with the powdery finish of mineral oxide. Cooler than patina, warmer than seafoam, with the archaeological weight of a mineral made by time.

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.

#28b4b8
Original
#a7abb8
Protanopia
#939db9
Deuteranopia
#00bab5
Tritanopia
#979797
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
2.53:1
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
8.31:1

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
##28B4B8
Display P3
Display P3
color(display-p3 0.3466 0.6958 0.7151)
P3 has subtle headroomOKLCH chroma 0.112

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.

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