Resonant Fluff Amaranth
Resonant Fluff Amaranth (#A21B04) is a deep red with a jewel character. It carries the deep, saturated richness of a gemstone. Authoritative and slightly formal, it works well for type and heavy UI elements. Its HSL profile (9°, 95%, 33%) places it in the highly saturated band at a dark 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 cyan. For something softer, pull in its analogous neighbors on either side of the wheel.
Etymology
Latin resonāns, echoing — present-participle of resonate, sharing root with sonance. As a color modifier, resonant implies a saturated-and-deep-vibrating quality where the hue carries low-frequency visual richness. Sits at the bold-and-resonant end of the grid, parallel to sonorous and resounding in usage.
Imitative-onomatopoeic origin, attested c. 1790. As a color modifier, fluff implies a soft-puffed-and-airy quality, the visual register of cotton-and-down-and-wool-fluff hand-carded-and-puffed cotton-and-down-and-wool-fluff hand-carded-and-puffed-fluff surfaces under hand-carded-and-puffed cotton-and-down-and-wool-fluff working-light. Sits at the modifier-and-texture end of the grid, parallel to down and fuzz in usage.
The genus Amaranthus — the grain crop and ornamental flower whose deep red-purple flower spikes give the color its name. Cultivated by the Aztecs as a ceremonial grain. The color refers to a fresh amaranth flower at peak bloom: a saturated, slightly cool deep red-purple with the matte finish of densely packed small flowers. Cooler than burgundy, warmer than wine.
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.