#371B33
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 #371B33 (Charcoal)
Classical color wheel pairings calculated from 360-degree rotational angles
Practical UI/UX Design Usage for #371B33
Primary Buttons & Focus Rings
With an RGB luminance of 55, 27, 51, this shade works excellently with white text (#FFFFFF) for call-to-action buttons and form focus states.
Background Containers
To use #371B33 as a card background or subtle surface tint, apply an opacity of 5% to 15% (bg-[#371B33]/10 in Tailwind) to maintain high typography readability.
Data Visualization & Badges
Pair with its complementary accent #1B371F or triadic partner #33371B to distinguish distinct categories in charts and tables.
Explore More Popular Colors
View All Colors Directory →Tools & Utilities for #371B33
Explore gradients, test contrast ratios, and generate monochromatic shades with #371B33
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Learn why digital colors look different when printed. Explore the physics of additive RGB light versus subtractive CMYK ink and how to avoid gamut clipping.