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Effective Konpeki

#4278a1
Notes

Effective Konpeki (#4278A1) is a true azure 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 (206°, 42%, 45%) 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 orange. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#4278a1
RGB
rgb(66, 120, 161)
HSL
hsl(206, 42%, 45%)
HWB
hwb(206 26% 37%)
OKLCH
oklch(55.3% 0.086 243.2)
P3
color(display-p3 0.3097 0.4654 0.6172)
HSV
hsv(206, 59%, 63%)
LAB
lab(48.46% -5.32 -27.42)
LCH
lch(48.46% 27.93 259.02)
CMYK
cmyk(59%, 25%, 0%, 37%)

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.

Konpeki
noun

Japanese konpeki (紺碧) — the saturated deep azure of clear ocean and sky. The compound combines kon (deep blue) and heki (jade-blue), naming a color deeper than aozora and brighter than ruri. The color refers to konpeki-painted Edo-period folding screens: a saturated, slightly cool deep blue with the matte finish of pigment in tempera.

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.

#4278a1
Original
#6678a3
Protanopia
#596fa0
Deuteranopia
#008286
Tritanopia
#6f6f6f
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).
AAon White
4.74:1
The quick brown foxSample body text at normal size. The wcag minimum for body contrast is 4.5:1 (AA) or 7:1 (AAA).
AA Largeon Black
4.43:1

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
##4278A1
Display P3
Display P3
color(display-p3 0.3097 0.4654 0.6172)
P3 has subtle headroomOKLCH chroma 0.086

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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