Hot Niche Seafoam
Hot Niche Seafoam (#18AC5D) is a true teal with a jewel character. It carries the deep, saturated richness of a gemstone. Authoritative and slightly formal, it works well for type and heavy UI elements. Its HSL profile (148°, 76%, 38%) 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 magenta. For something softer, pull in its analogous neighbors on either side of the wheel.
Etymology
Old English hāt, of high temperature — applied metaphorically to color since the eighteenth century for warm hues at high saturation. Hot pink, hot red: the implication is luminous intensity combined with thermal warmth. Sits in the bright-and-warm corner of the grid, alongside burning and vivid.
Italian nicchia, recess. As a color modifier, niche implies a wall-recess-for-statue-or-icon quality, the visual register of Roman-Catholic-and-Renaissance-niche hand-cut wall-recess-and-shell-shaped niche-for-statue-or-icon architectural surfaces under candle-and-niche-statue-and-icon devotional light. Sits at the modifier-and-architecture end of the grid, parallel to alcove and atrium in usage.
The pale, slightly translucent green-blue of foam on a breaking wave — light scattered through micron-scale air bubbles in salt water, with a touch of the sea's color showing through. Seafoam green refers specifically to that desaturated tint: a soft, very pale green-blue with the optical lightness of small bubbles in motion. Lighter than mint, cooler than celadon.
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.
Wide gamut
The CSS Color 4 wide-gamut form of this color. Both swatches render the same color on every display — the P3 form only diverges from sRGB when a designer pushes channels outside sRGB's reach.
Moderately saturated colors gain a small bump in P3 — the difference is usually visible side-by-side on wide-gamut hardware but won't change the character of the color.