colors
Back to gallery

Bold Amur

#4057b4
Notes

Bold Amur (#4057B4) is a true blue 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 (228°, 48%, 48%) 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
#4057b4
RGB
rgb(64, 87, 180)
HSL
hsl(228, 48%, 48%)
HWB
hwb(228 25% 29%)
OKLCH
oklch(49.0% 0.150 269.7)
HSV
hsv(228, 64%, 71%)
LAB
lab(39.92% 21.51 -52.13)
LCH
lch(39.92% 56.40 292.42)
CMYK
cmyk(64%, 52%, 0%, 29%)

Etymology

Bold
adjective

Old English beald, brave, courageous — a quality word that crossed over to color in the late seventeenth century. Bold describes a color that asserts itself: high saturation combined with mid lightness, where the hue presents itself without compromise. Sits at the center of the bold-bucket grid, near strong and rich. Closer to a presence word than a pigment word.

Amur
noun

The river forming the border between Russia and China — and the saturated deep blue of Amur River water at Khabarovsk and the surrounding Russian Far East taiga sky. Amur refers to mid-depth Amur River water at Khabarovsk: a saturated, slightly cool deep blue with the optical complexity of cold-temperate continental river.

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.

#4057b4
Original
#2063b7
Protanopia
#0059b2
Deuteranopia
#006d7d
Tritanopia
#595959
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
6.48:1
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
3.24:1

Related Colors

Canvas