Vibrant Uguisu
Vibrant Uguisu (#5FB442) is a true green 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 (105°, 46%, 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 violet. 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.
Horornis diphone, the Japanese bush warbler — and the slightly muted olive-yellow of the bird's plumage. Uguisu-iro is a traditional Japanese color used in tea-ceremony pottery and fukusa silk wraps. The color refers to a fresh-molted bush warbler: a soft, slightly muted yellow-green with the matte finish of small bird feathers. Cooler than wakaba.
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.