#b81f18
Thunderbird
Closest match (97% match)
Color formats
RGB
rgb(184, 31, 24)
Red, Green, Blue components
HSL
hsl(3, 77%, 41%)
Hue, Saturation, Lightness
CMYK
cmyk(0, 83, 87, 28)
Print color encoding
Luminance
0.112
Relative luminance
Variations
Shades (Darkening)
Tints (Lightening)
Tones (Reduced saturation)
Harmonies
Click the color slices to copy the code.
Complementary (Opposite)
#b81f18
#18b1b8
Analogous (Adjacent)
#b81861
#b81f18
#b86f18
Triadic
#b81f18
#18b81f
#1f18b8
Split complementary
#b81f18
#18b86f
#1861b8
Complete conversion table
HEX
#B81F18
RGB
rgb(184,31,24)
RGBA
rgba(184,31,24, 1)
HSL
hsl(2.63,76.92%,40.78%)
OKLCH (Modern CSS)
oklch(0.51 0.19 28.8)
CSS Variable
--color: #b81f18;
CMYK
C: 0% M: 83% Y: 87% K: 28%
Note: Converting web (RGB) colors to print (CMYK) colors is never 100 percent accurate due to physical limitations. Always request a test print before production.
Android ARGB
0xFFB81F18
Swift UIColor
UIColor(red: 0.72, green: 0.12, blue: 0.09, alpha: 1.0)
Decimal (int)
12066584
JSON
{ "color": "#B81F18" }
CIE LAB
L: 40.0 a: 58.2 b: 44.1
CIE LCH
L: 40.0 C: 73.0 H: 37.2
CIE XYZ
N/A
Preview
Readability and Typography
Headline Test
This text demonstrates the reading experience on this background color.
Headline Test
This text demonstrates the reading experience on this background color.
UI Component Set
This is an example alert bar using the selected color.
Product Mockup
4582 •••• •••• 9018
CARDHOLDER
JOHN DOE
VALID
12/28
Mobile application
Customer support
Hi! How can we help you today?
I love this new color! 😍
Data visualization
Weekly growth
+1,240
12.5%1D
1W
1M
WED
2,450
Contrast
Contrast and readability (WCAG)
On white background
6.47
Small text (14pt)
The quick brown fox jumps over...
AA
AAA
Large text or UI (18pt Bold)
AA
AAA
On black background
3.25
Small text (14pt)
The quick brown fox jumps over...
AA
AAA
Large text or UI (18pt Bold)
AA
AAA
Color blindness simulator
ORIG
SIM
Protanopia (red)
ORIG
SIM
Deuteranopia (green)
ORIG
SIM
Tritanopia (blue)
ORIG
SIM
Monochrome (color blind)
Mixing guide
How to mix this color using physical paints or printing inks.
MIXING PALETTE
74%
23%
3%
RYB PIGMENTS
Cadmium red
Pigment
74%
Ivory black
Pigment
23%
Cadmium yellow
Pigment
3%
Unlike light, mixing paints makes colors darker. This simulation mimics the behavior of physical pigments.
INK LEVELS
87%
P
83%
MAGENTA
28%
KEY
CMYK INKS
Yellow
Ink
87%
Magenta
Ink
83%
Black (Key)
Ink
28%
Physical properties
Perceptual and light-related properties derived from the digital color.
Spectral relationship
Red hue
620–750 nm • closest visible-spectrum range
750 nm
380 nm
Visual temperature
Warm
A perceptual warm–cool classification. Kelvin does not apply to an arbitrary interface color.
Cool
Neutral
Warm
Luminance (brightness)
11.2%
Dark • relative luminance
0%
50%
100%
An RGB color is produced by combined screen light, so this range is a visual comparison rather than an exact physical wavelength.
Gradient gallery
Generate premium CSS backgrounds and textures from your color.
Similar & Related Colors
Mathematically computed harmonies, shades, and similar tones for this color.