Light Slate Gray and Slate Grey are near-identical blue shades — they sit within a few degrees of hue, lightness, and saturation of each other. The difference is mostly in name and historical use. Light Slate Gray and Slate Grey are near-identical blue shades — they sit within a few degrees of hue, lightness, and saturation of each other. The difference is mostly in name and historical use. Light Slate Gray (#778899) has an HSL of 210°, 14%, 53%, whereas Slate Grey (#708090) sits at 210°, 13%, 50%.
Four real design scenarios, with the recommended pick based on hue, saturation, and WCAG contrast.
Light Slate Gray is more saturated (14% HSL vs 13%) so it reads as bolder and more memorable at logo scale, while Slate Grey can feel washed out when printed small.
Slate Grey hits a 4.05:1 WCAG contrast against white — safer for text-heavy interfaces — where Light Slate Gray only reaches 3.64:1 and risks failing AA at small body sizes.
Light Slate Gray is a cool-leaning tone that flatters spring/summer collections and warmer skin undertones, while Slate Grey leans cooler and is better suited to autumn/winter layering.
Slate Grey is the more muted of the two (13% saturation) and sits more calmly on large wall surfaces, while Light Slate Gray's higher chroma can overwhelm a room when used beyond accent pieces.
Light Slate Gray (#778899) is a medium, near-neutral blue with a cool undertone — it feels balanced, versatile and desaturated and restrained.
Slate Grey (#708090) is a medium, near-neutral blue with a cool undertone — it feels balanced, versatile and desaturated and restrained.
Text legibility depends on the contrast ratio between foreground and background. WCAG 2.1 AA requires at least 4.5:1 for normal text and 3:1 for large text; AAA requires 7:1. Use these numbers to choose accessible combinations for your design.
Each color has a dedicated page with shades, tints, CSS name, pairings, and color psychology.