Punchy Idanthrene
Punchy Idanthrene (#0D5CD7) is a true azure with a neon character. It sits at the high-saturation edge of its family. Use it sparingly, as signage, accent, or highlight against darker surfaces. Its HSL profile (217°, 89%, 45%) 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
A modern adjectival form of punch, to strike sharply. Used as a color word since the early twentieth century for hues that read as highly contrasting and visually loud. Punchy red, punchy yellow: the implication is full saturation combined with optical impact. Sits across the bold and bright buckets, near vivid and striking.
The trade name for vat blue synthetic dyes — particularly Idanthrene Blue RS (BASF, 1901), a polycyclic aromatic dye that displaced indigo for many industrial textile applications. The color refers to Idanthrene-dyed industrial cotton: a saturated, slightly cool deep blue with the matte finish of synthetic-pigment-and-cotton.
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.