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Coolazure

Warm Sapphire Thread

#638aca
Notes

Warm Sapphire Thread (#638ACA) is a true azure 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 (217°, 49%, 59%) 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 amber. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#638aca
RGB
rgb(99, 138, 202)
HSL
hsl(217, 49%, 59%)
HWB
hwb(217 39% 21%)
OKLCH
oklch(63.2% 0.106 260.0)
HSV
hsv(217, 51%, 79%)
LAB
lab(57.17% 4.53 -37.27)
LCH
lch(57.17% 37.54 276.93)
CMYK
cmyk(51%, 32%, 0%, 21%)

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

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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.

#638aca
Original
#718fcd
Protanopia
#6585c9
Deuteranopia
#3298a1
Tritanopia
#868686
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
3.49:1
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
6.02:1

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