Substantial Foxglove
Substantial Foxglove (#5363F0) is a true blue with a vibrant character. It holds its own as a focal accent, carrying visual weight without tipping into neon territory. Its HSL profile (234°, 84%, 63%) 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
Latin substantia, substance — adjectival suffix -al, derived from sub-stāre (to stand under). As a color modifier, substantial implies a saturated-and-weighty-and-material quality where the hue carries visual mass and presence. Sits at the bold-and-weighty end of the grid, parallel to weighty and hefty in usage.
Digitalis purpurea, the European biennial whose tall spires of tubular flowers contain digitoxin, the heart-medicine glycoside that's still in clinical use. The color refers to a fresh deep-purple foxglove flower interior: a saturated, slightly red-shifted deep purple with the matte finish of a tubular bee-pollinated bloom. Cooler than mauve, warmer than indigo, with the medicinal weight of a plant lethal in raw form and lifesaving in measured dose.
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.