Slate 900
slate-900 · #0F172A
HEX
#0F172A
RGB
rgb(15, 23, 42)
CMYK
cmyk(64%, 45%, 0%, 84%)
HSL
hsl(222, 47%, 11%)
LAB
lab(8.0, 3.3, -14.1)
What is Slate 900?
Slate 900 is the slate-900 reference in the Tailwind CSS palette. Its sRGB value is #0F172A (rgb 15, 23, 42). It sits in the neutral family. The default color palette shipped with Tailwind CSS v3 by Tailwind Labs. 22 color families across 11 lightness steps (50 to 950). See disclaimer for accuracy and trademark notes.
Accessibility
WCAG 2.1 contrast checks for Slate 900 as a background.
Black text on this color
White text on this color
Shades, tints & tonal scale of Slate 900
An 11-step tonal scale derived from Slate 900 (#0F172A). Click any swatch to copy its HEX. Use these as a starting point for design tokens, hover states, and disabled states in a design system.
50
#ECECEE
#ECECEE
100
#D9DADD
#D9DADD
200
#B2B5BB
#B2B5BB
300
#878B95
#878B95
400
#4B515F
#4B515F
500
#0F172A
#0F172A
600
#0D1424
#0D1424
700
#0A0F1B
#0A0F1B
800
#070A13
#070A13
900
#04060B
#04060B
950
#020305
#020305
Lighter tints (mixed with white)
15%
#6D6E72
30%
#969698
45%
#B3B4B5
60%
#CCCCCD
75%
#E1E1E1
Darker shades (mixed with black)
15%
#0D1526
30%
#0B1222
45%
#090F1E
60%
#060B18
75%
#040711
Color harmonies for Slate 900
Classic color-theory harmonies derived from rotating the hue of Slate 900. Use these to build accent palettes, brand systems, and accessible UI color pairings.
Complementary
180° opposite — strongest contrast
#0F172A
#0F172A
#29210F
#29210F
Triadic
Three colors 120° apart
#0F172A
#0F172A
#290F17
#290F17
#17290F
#17290F
Analogous
Two neighbors ±30° on the wheel
#0F2429
#0F2429
#0F172A
#0F172A
#140F29
#140F29
Split-complementary
Base + two colors flanking its complement
#0F172A
#0F172A
#29140F
#29140F
#24290F
#24290F
Tetradic
Two complementary pairs
#0F172A
#0F172A
#210F29
#210F29
#29210F
#29210F
#17290F
#17290F
Square
Four colors evenly spaced 90° apart
#0F172A
#0F172A
#290F24
#290F24
#29210F
#29210F
#0F2914
#0F2914
Slate 900 in every color space
Full conversion of Slate 900 across the color spaces designers and developers actually use — including OKLCH (the perceptually-uniform space that powers Tailwind v4 and CSS Color Module Level 4) and HWB.
HEX
#0F172A
RGB
rgb(15, 23, 42)
CMYK
cmyk(64%, 45%, 0%, 84%)
HSL
hsl(222, 47%, 11%)
HSV
hsv(222, 64%, 16%)
HWB
hwb(222 6% 84%)
CIE Lab
lab(8.0 3.3 -14.1)
OKLCH
oklch(20.8% 0.040 265.8)
XYZ (D65)
xyz(0.92, 0.88, 2.31)
Copy-ready code for Slate 900
Drop-in snippets for CSS, Tailwind, Sass, iOS Swift, and Android XML. Click the copy button on any snippet to put it on your clipboard.
CSS
color: #0F172A;
background-color: #0F172A;CSS variable
:root {
--color-slate-900: #0F172A;
}Tailwind config
// tailwind.config.js
colors: {
'slate-900': '#0F172A',
}Sass
$color-slate-900: #0F172A;Swift UIColor
UIColor(red: 0.059, green: 0.090, blue: 0.165, alpha: 1.0)Android XML
<color name="slate-900">#0F172A</color>Closest match in every color system
The nearest Slate 900 equivalent in every other color system on this site, ranked by ΔE2000 perceptual distance. Useful when translating between design-system, web-standard, and industrial color references.
Closest in Tailwind CSS palette
Top 6 ΔE2000-closest entries within the same collection.
Closest Pantone matches
Top 6 ΔE2000-closest Pantone references. Cross-system matching is approximate — see disclaimer.
Closest RAL Classic matches
Top 6 ΔE2000-closest RAL Classic references for industrial coating cross-reference.
RAL 5003
#1D1E33
Sapphire blue
RAL 5013
#1E213D
Cobalt blue
RAL 5004
#18171C
Black blue
RAL 5008
#26252D
Grey blue
RAL 5010
#0E294B
Gentian blue
RAL 5011
#231A24
Steel blue
FAQ about Slate 900
What is the HEX code for Slate 900?
Slate 900 (slate-900) has the HEX code #0F172A. In RGB it is rgb(15, 23, 42), and in CMYK it is cmyk(64%, 45%, 0%, 84%).
What is the OKLCH value of Slate 900?
Slate 900 converts to oklch(0.208 0.040 265.8). OKLCH is the perceptually uniform color space used by Tailwind v4 and CSS Color Module Level 4.
Is Slate 900 accessible for body text?
Used as a background, Slate 900 has a contrast ratio of 1.18:1 with black text and 17.85:1 with white text. WCAG 2.1 AA requires 4.5:1 for normal text. The current recommendation is to use white text and verify in real UI context.
What is the closest Pantone to Slate 900?
The closest Pantone reference to Slate 900 by ΔE2000 perceptual distance is Pantone 281 C (#0C2340). Cross-system Pantone matching is approximate; for color-critical print work, verify with a physical Pantone guide.
What is the closest RAL color to Slate 900?
The closest RAL Classic reference to Slate 900 by ΔE2000 distance is RAL 5003 (Sapphire blue, #1D1E33). RAL is a German industrial coating standard commonly used for paint, powder coat, and architectural specification.
What is the complementary color of Slate 900?
The complementary color (180° opposite on the HSL color wheel) of Slate 900 is #29210F. Use it for high-contrast accents, error states, or call-to-action pairings.
Data provenance & source
Tailwind CSS default palette (v3)
The default color palette shipped with Tailwind CSS v3 by Tailwind Labs Inc. Use as a reference for design tokens, web color systems, and Tailwind-based design conversations. Names like 'blue-500' are the project's own naming convention.
- Source type
- derived
- Confidence
- high
- License
- MIT
- Last reviewed
- 2026-05-24
Workflow tags
Tailwind palette values are designed for digital interfaces under sRGB. For print, convert to a process-appropriate value and proof against the substrate; do not rely on sRGB CMYK conversion for color-critical print work.