Frenetic Sulfur
Frenetic Sulfur (#A4A839) is a true yellow 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 (62°, 49%, 44%) 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 blue. For something softer, pull in its analogous neighbors on either side of the wheel.
Etymology
Greek phrenitikós, frenzied — adjectival suffix -ic, derived from phrēn (mind). As a color modifier, frenetic implies a saturated-and-frenzied-and-active quality, the bright color of Hyper-Color-and-Memphis-Group 1980s-design saturated-and-active visual-rhythm. Sits at the bright-and-active end of the grid, parallel to frantic and manic in usage.
Element S, atomic number 16 — bright yellow crystalline mineral around volcanic vents from Sicily to Hokkaidō. Pure sulfur dust gave its color to the explosive mixtures of medieval gunpowder and to the fungicide vineyards of nineteenth-century France. The color is the surface of a freshly cleaved sulfur crystal: a saturated, slightly green-shifted yellow with the resinous finish of the elemental mineral.
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.