Effective Celadon
Effective Celadon (#B4F6BB) is a soft green with a pastel character. It reads calm and airy, with enough chroma to feel intentional rather than washed out. Its HSL profile (126°, 79%, 84%) places it in the highly saturated band at a light 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 violet. For something softer, pull in its analogous neighbors on either side of the wheel.
Etymology
Latin effectīvus, productive — adjectival suffix -ive. As a color modifier, effective implies a clear-and-purpose-achieving quality where the hue carries the visual register of successful-task-completion design-element. Sits at the crisp-and-functional end of the grid, parallel to practical and useful in usage.
The pale-green iron-ash glaze fired on Chinese and Korean stoneware since the Han dynasty — Goryeo celadon and Longquan ware reaching their peak between the tenth and thirteenth centuries. The color refers to a glazed Goryeo bowl in display lighting: a soft, slightly muted green-blue with the high shine of vitrified silica. Cooler than jade, warmer than seafoam, with the museum weight of a ceramic tradition prized in East Asian imperial courts.
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.