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Magisterial Helio

#a66de4
Notes

Magisterial Helio (#A66DE4) is a true indigo 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 (269°, 69%, 66%) 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 lime. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#a66de4
RGB
rgb(166, 109, 228)
HSL
hsl(269, 69%, 66%)
HWB
hwb(269 43% 11%)
OKLCH
oklch(64.6% 0.177 304.0)
P3
color(display-p3 0.6187 0.4373 0.8672)
HSV
hsv(269, 52%, 89%)
LAB
lab(56.73% 45.56 -52.24)
LCH
lch(56.73% 69.32 311.09)
CMYK
cmyk(27%, 52%, 0%, 11%)

Etymology

Magisterial
adjective

Latin magisterium, teacher's office — adjectival suffix -al. As a color modifier, magisterial implies a saturated-and-authoritative-and-formal quality, the deep-rich color of Qing-dynasty civil-magistrate court-and-ritual textiles and Imperial-Examination scholar-class livery. Sits at the bold-and-authoritative end of the grid, parallel to authoritative and commanding.

Helio
noun

A shortened form of heliotrope — sometimes used as a slightly more genteel color name in late-Victorian fashion catalogues, particularly for the pale lavender-purple silks of mourning dress's transition out of full black. The color refers to a Victorian Helio silk: a soft, slightly muted pale purple with the satiny finish of a fabric dyed to register a specific point in the mourning calendar. Lighter than mauve, cooler than lilac.

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.

#a66de4
Original
#4587e8
Protanopia
#5788e1
Deuteranopia
#9b839e
Tritanopia
#828282
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).
AA Largeon White
3.54:1
The quick brown foxSample body text at normal size. The wcag minimum for body contrast is 4.5:1 (AA) or 7:1 (AAA).
AAon Black
5.93:1

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
##A66DE4
Display P3
Display P3
color(display-p3 0.6187 0.4373 0.8672)
P3 has subtle headroomOKLCH chroma 0.177

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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