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Bulky Tetsukon

#337ffc
Notes

Bulky Tetsukon (#337FFC) 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 (217°, 97%, 59%) 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 amber. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#337ffc
RGB
rgb(51, 127, 252)
HSL
hsl(217, 97%, 59%)
HWB
hwb(217 20% 1%)
OKLCH
oklch(61.9% 0.201 260.0)
HSV
hsv(217, 80%, 99%)
LAB
lab(54.98% 20.78 -68.80)
LCH
lch(54.98% 71.87 286.81)
CMYK
cmyk(80%, 50%, 0%, 1%)

Etymology

Bulky
adjective

Old Norse búlki, cargo / mass — adjectival suffix -y. As a color modifier, bulky implies a saturated-and-massive-and-occupying quality where the hue takes up visual space with broad-and-heavy presence. Sits at the bold-and-weighty end of the grid, parallel to hefty and substantial in usage.

Tetsukon
noun

Japanese tetsukon (鉄紺) — iron navy, the saturated dark blue of Meiji-period samurai ceremonial robes and the kasuri (ikat) textiles of pre-modern rural Japan. The color refers to a tetsukon-dyed kasuri cotton: a deep, slightly cool dark blue with the matte finish of multi-bath dyed cotton.

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.

#337ffc
Original
#308dff
Protanopia
#007bfa
Deuteranopia
#009db2
Tritanopia
#787878
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
3.76:1
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
5.58:1

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