colors
Back to gallery

Pulsing Rhine

#3397df
Notes

Pulsing Rhine (#3397DF) is a true azure with a vibrant character. It holds its own as a focal accent, carrying visual weight without tipping into neon territory. Its HSL profile (205°, 73%, 54%) 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
#3397df
RGB
rgb(51, 151, 223)
HSL
hsl(205, 73%, 54%)
HWB
hwb(205 20% 13%)
OKLCH
oklch(65.3% 0.140 244.6)
HSV
hsv(205, 77%, 87%)
LAB
lab(60.03% -4.22 -44.65)
LCH
lch(60.03% 44.85 264.60)
CMYK
cmyk(77%, 32%, 0%, 13%)

Etymology

Pulsing
adjective

The progressive participle of pulse, to throb. Used as a color modifier for hues that read as if they were alternating between two states of luminance — the vibration of a high-saturation color against a contrasting background. Sits in the bright-bucket center alongside electric, with the implication of optical motion rather than static luminance.

Rhine
noun

The Rhine River — Europe's third-longest, flowing from the Swiss Alps to the Dutch North Sea. Rhine color refers to mid-depth Rhine River water at Lorelei on the Mittelrhein: a saturated, slightly cool deep blue with the optical depth of Alpine-glacier-fed European river water.

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.

#3397df
Original
#7699e2
Protanopia
#5d8ade
Deuteranopia
#00a9b1
Tritanopia
#878787
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
3.17:1
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
6.63:1

Related Colors

Canvas