Tough Spark Ruby
Tough Spark Ruby (#C4387E) is a true magenta 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 (330°, 56%, 49%) 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 teal. For something softer, pull in its analogous neighbors on either side of the wheel.
Etymology
Old English tōh, firm / tenacious — sharing root with German zäh. As a color modifier, tough implies a saturated-and-resilient quality where the hue resists fading-and-modulation through its strong pigmentation. Sits at the bold-and-resilient end of the grid, parallel to rugged and hardy in usage.
Old English spearca, small-ember. As a color modifier, spark implies a small-bright-and-flying-ember quality, the visual register of blacksmith-anvil-and-bonfire-spark hand-small-bright-and-flying-ember blacksmith-anvil-and-bonfire-and-flint-strike sparked-and-small-bright-and-flying surfaces under blacksmith-anvil-and-bonfire-and-flint-strike orange-glow-and-iron-and-flint forge-and-hearth-light. Sits at the modifier-and-mood end of the grid, parallel to flash and flare in usage.
From the Latin ruber — simply, red. The gemstone is a chromium-tinged corundum, harder than anything in nature except diamond, and so saturated that a fine Burmese pigeon's blood ruby at auction outpaces a comparable diamond by weight. The color borrows the gem's confidence: a clear, glassy red without the brown of garnet or the blue of crimson.
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.