#25303A
Approximate Color Name: Charcoal
Closest CSS Color Name: DarkSlateGray (#2F4F4F)
Color Space Coordinates
Copyable codes for development, CSS styling, and print
WCAG 2.1 Contrast & Accessibility Audit
Evaluates readability standards for normal body text (4.5:1 AA / 7.0:1 AAA) and large headings (3.0:1 AA / 4.5:1 AAA)
Tonal Variations (Shades, Tints & Tones)
Calibrated step variations created by adding black (shades), white (tints), and gray (tones)
Harmonies for #25303A (Charcoal)
Classical color wheel pairings calculated from 360-degree rotational angles
Practical UI/UX Design Usage for #25303A
Primary Buttons & Focus Rings
With an RGB luminance of 37, 48, 58, this shade works excellently with white text (#FFFFFF) for call-to-action buttons and form focus states.
Background Containers
To use #25303A as a card background or subtle surface tint, apply an opacity of 5% to 15% (bg-[#25303A]/10 in Tailwind) to maintain high typography readability.
Data Visualization & Badges
Pair with its complementary accent #3B3026 or triadic partner #3B2631 to distinguish distinct categories in charts and tables.
Explore More Popular Colors
View All Colors Directory →Tools & Utilities for #25303A
Explore gradients, test contrast ratios, and generate monochromatic shades with #25303A
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