Vibrant Bachelorbutton
Vibrant Bachelorbutton (#518BFC) 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 (220°, 97%, 65%) 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.
Etymology
From the Latin vibrare, to shake — used as a color word since the seventeenth century for hues that read as alive and resonant. Vibrant orange, vibrant green: the implication is saturation combined with the optical impression of slight motion or energy. Sits at the bright-bucket center alongside vivid and lively.
Centaurea cyanus, the cultivar of cornflower bred for cottage-garden use — also called bachelor's button for its traditional use in the buttonhole of an unmarried man's coat. The color refers to a fresh bachelor's button bloom in summer: a saturated, slightly cool deep blue with the matte finish of small clustered ray-and-disc-florets.
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 exploreHarmonies
Accessibility
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.
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.
Wide gamut
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.
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.