Brilliant Sumatra
Brilliant Sumatra (#51B152) is a true green with a cool character. It leans cool, sitting on the blue, green, and violet side of the wheel. Quiet and dependable, a fit for product UI and data visualization. Its HSL profile (121°, 38%, 51%) 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 Italian brillante, sparkling — used as a color modifier since the seventeenth century for hues that read as optically active beyond their literal saturation. Brilliant green, brilliant blue: the implication is luminance combined with the slight sparkle of a high-refractive surface. Sits at the bright-bucket center alongside vivid and bright.
The Indonesian island — home to the Sumatran orangutan, tiger, and rhinoceros — and the deep green of Sumatran rainforest and Coffea arabica coffee plantations. Sumatra color refers to a Sumatran highland coffee plantation: a saturated, slightly cool deep green with the matte finish of broad-leaved coffee shrubs.
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.