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Smoldering Vladivostok

#378bf0
Notes

Smoldering Vladivostok (#378BF0) is a true azure with a neon character. It sits at the high-saturation edge of its family. Use it sparingly, as signage, accent, or highlight against darker surfaces. Its HSL profile (213°, 86%, 58%) places it in the highly saturated band at a mid lightness. Best used in small doses, like logos, CTAs, focus rings, or highlight text, where its saturation becomes a feature rather than noise. 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
#378bf0
RGB
rgb(55, 139, 240)
HSL
hsl(213, 86%, 58%)
HWB
hwb(213 22% 6%)
OKLCH
oklch(63.7% 0.171 255.2)
P3
color(display-p3 0.3080 0.5380 0.9127)
HSV
hsv(213, 77%, 94%)
LAB
lab(57.62% 9.43 -57.91)
LCH
lch(57.62% 58.67 279.25)
CMYK
cmyk(77%, 42%, 0%, 6%)

Etymology

Smoldering
adjective

The progressive participle of smolder, to burn slowly without flame. Used as a color word since the late nineteenth century for the deep reds and oranges of barely-flame coal — the warm saturated darks where the heat is internal rather than emitted. Sits in the bold-and-warm corner, slightly less luminous than burning and slightly less calm than rich.

Vladivostok
noun

The Russian Pacific Far East port city — and the saturated deep blue of Amursky Bay and Vladivostok Harbor on the Sea of Japan. Vladivostok refers to the harbor water at midday: a saturated, slightly cool deep blue with the optical depth of cold-water Pacific port.

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.

#378bf0
Original
#5993f4
Protanopia
#3783ee
Deuteranopia
#00a3b2
Tritanopia
#808080
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
3.43:1
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
6.11:1

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
##378BF0
Display P3
Display P3
color(display-p3 0.3080 0.5380 0.9127)
P3 has subtle headroomOKLCH chroma 0.171

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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