Signal black RAL 9004
Color values
HEX #282828
RGB 40, 40, 40
HSL 0°, 0%, 16%
Series Whites & Blacks
All formats
HEX #282828
RGB rgb(40, 40, 40)
HSL hsl(0, 0%, 16%)
CSS var --color: #282828;
RAL RAL 9004
Color analysis
Temperature Neutral
Luminance 2%
Saturation 0%
Brightness 16%
WCAG accessibility
On white background
Aa — The quick brown fox jumps over the lazy dog
14.74:1
AA Pass
AA large Pass
AAA Pass
AAA large Pass
On black background
Aa — The quick brown fox jumps over the lazy dog
1.42:1
AA Fail
AA large Fail
AAA Fail
AAA large Fail
Tint & shade scale
Use this color in other tools
Where it's used
A deep signal black used in safety markings, industrial labeling, and architectural metalwork. High-opacity finish, pairs with RAL 9003 and RAL 9010.
About this color
RAL 9004 Signal black is a RAL Classic color with HEX value #282828, RGB(40, 40, 40), HSL(0°, 0%, 16%). It belongs to the Whites & Blacks family (RAL 9xxx series). WCAG relative luminance: 2%. Contrast on white: 14.74:1. Contrast on black: 1.42:1.
FAQ
RAL 9004 Signal black is a standardized color from the RAL Classic palette, used in industry, architecture, and design for consistent color communication. Its HEX value is #282828, equivalent to RGB(40, 40, 40).
The HEX code of RAL 9004 Signal black is #282828. In CSS you can use it directly: color: #282828; or background-color: #282828;. Its RGB equivalent is rgb(40, 40, 40) and HSL is hsl(0, 0%, 16%).
RAL codes (e.g. RAL 9004) are physical paint standards created for industrial use — they define exact pigment formulations. HEX codes (e.g. #282828) are digital representations for screens. The conversion is approximate: the same HEX can look different on screens vs. painted surfaces due to lighting, texture, and pigment variance.
WCAG contrast ratio compares the relative luminance of two colors: (L1+0.05)/(L2+0.05), where L is calculated from linearized RGB values. RAL 9004 Signal black has a relative luminance of 2%, giving a contrast of 14.74:1 on white and 1.42:1 on black. AA requires ≥4.5:1 for normal text.
The HEX value #282828 is the closest digital approximation of RAL 9004 Signal black, but not an exact physical match. RAL colors are defined by spectrophotometric measurements of physical paint samples. On-screen rendering depends on your monitor calibration, color profile, and ambient lighting.
RAL 9004 Signal black (HEX #282828) is used in industrial coatings, architectural finishes, signage, and product design wherever whites & blacks tones are needed. RAL Classic codes are the standard reference in European manufacturing, construction, and powder coating industries.
RAL Classic contains 215 standardized colors organized into 9 series by hue family: yellows/beiges (1xxx), oranges (2xxx), reds (3xxx), violets (4xxx), blues (5xxx), greens (6xxx), greys (7xxx), browns (8xxx), and whites/blacks (9xxx). RAL 9004 belongs to the Whites & Blacks family.