Serene Nereid Sky
Serene Nereid Sky (#87DBFE) is a soft cyan 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 (198°, 98%, 76%) 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 orange. For something softer, pull in its analogous neighbors on either side of the wheel.
Etymology
Latin serēnus, clear / unclouded. As a color modifier, serene implies a clear-and-untroubled quality where the hue carries the visual register of cloudless-bright-day atmospheric stability. Sits at the crisp-and-calm end of the grid, parallel to placid and untroubled in usage.
Greek Νηρηΐς, sea-nymph-daughter-of-Nereus. As a color modifier, nereid implies a sea-nymph-and-Aegean-foam quality, the visual register of Hellenic-Nereid-and-Aegean-sea-nymph hand-sea-nymph-and-Aegean-foam Hellenic-Nereid-and-Aegean-sea-nymph-and-Poseidon-court nereid-and-sea-nymph-and-Aegean-foam surfaces under Hellenic-Nereid-and-Aegean-sea-nymph-and-Poseidon-court Aegean-island-and-rocky-cove sea-nymph-light. Sits at the modifier-and-myth end of the grid, parallel to nymph and dryad in usage.
The blue of a clear sky at noon — produced by Rayleigh scattering, the preferential dispersion of shorter wavelengths through atmospheric molecules. Air itself is colorless; the color we see is sunlight scattered toward our eyes by every cubic kilometer above. The reference shade is mid-latitude noon under a high pressure system: a clean, slightly green-shifted blue with the luminous depth of light scattered across an entire hemisphere of air.
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.