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Honest Helio

#643d84
Notes

Honest Helio (#643D84) is a true indigo with an earthy character. It leans grounded and natural, the kind of color that plays well with wood, clay, linen, and warm neutrals. Its HSL profile (273°, 37%, 38%) 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
#643d84
RGB
rgb(100, 61, 132)
HSL
hsl(273, 37%, 38%)
HWB
hwb(273 24% 48%)
OKLCH
oklch(43.9% 0.119 307.6)
P3
color(display-p3 0.3705 0.2461 0.5017)
HSV
hsv(273, 54%, 52%)
LAB
lab(33.38% 31.48 -33.51)
LCH
lch(33.38% 45.98 313.21)
CMYK
cmyk(24%, 54%, 0%, 48%)

Etymology

Honest
adjective

Latin honestus, honorable — used as a color modifier since the seventeenth century for hues that read as straightforward and unembellished, the working browns and grays of vernacular architecture rather than the polished shades of court fashion. Honest brown, honest gray: moderate saturation combined with optical directness. Sits at the crisp-bucket alongside plain and frank.

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.

#643d84
Original
#284d86
Protanopia
#344f82
Deuteranopia
#5f495a
Tritanopia
#4a4a4a
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
8.26:1
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
2.54:1

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
##643D84
Display P3
Display P3
color(display-p3 0.3705 0.2461 0.5017)
P3 has subtle headroomOKLCH chroma 0.119

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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