Closest to Dark Slate Blue
#303F9F
Color conversions
Reference values for common CSS, design, and accessibility formats.
| Format | Value | Preview | Copy |
|---|---|---|---|
| HEX | 303F9F | ||
| HEX with # | #303F9F | ||
| RGB | rgb(48, 63, 159) | ||
| RGBA | rgba(48, 63, 159, 1) | ||
| HSL | hsl(231.89 53.62% 40.59%) | ||
| HSLA | hsla(231.89, 53.62%, 40.59%, 1) | ||
| HSV | hsv(231.89, 69.81%, 62.35%) | ||
| CMYK | cmyk(69.81%, 60.38%, 0%, 37.65%) | ||
| OKLCH | oklch(41.64% 0.1556 271.17) |
Closest named matches
Color modifications
Lighter shades
Saturation steps
Suggested pairings
Split-complementary
Try this combo as a gradientUse this color in CSS
--color: #303F9F;
bg-[#303f9f]
Accessibility quick-check
White text
8.98:1
AAA normal
Black text
2.34:1
Decorative only
Reference notes
#303F9F is a balanced, clear blue color closest to Dark Slate Blue. The color has RGB channels of 48, 63, and 159; in HSL terms, it is centered near 232 degrees with 54% saturation and 41% lightness. In a design system, this cool reading is a useful shortcut for deciding whether the color should act as a primary accent, a supporting surface, or a quiet divider. The safest usage pattern is to test it against both light and dark surfaces, then reserve the weaker text pairing for decoration rather than essential labels. If the color feels too forceful at full strength, the lighter, darker, and desaturated variants usually provide a calmer path for production UI. For editorial or product interfaces, reserve the most saturated use for accents and repeat softer variants in borders, labels, or background fills. This makes it useful for backgrounds, supporting UI surfaces, editorial layouts, and restrained visual systems. In CSS systems, define it as a custom property first so variations, shadows, and gradients can stay consistent.