Cobalt
#04288B · Cobalt
#04288B is Cobalt, a cool blue color. It has an RGB value of 4, 40, 139 and a relative luminance of 0.034, making it a dark surface.
Temperature
❄ Cool
Hue family
blue
Luminance
0.03
Conversions
HEX
RGB
HSL
HSV
CMYK
OKLCHPro
Contrast & accessibility
On white
The quick fox
12.49:1
AA normal✓
AA large✓
AAA normal✓
On black
The quick fox
1.68:1
AA normal✕
AA large✕
AAA normal✕
Color harmonies
Complementary
Split-complementary
Shades & tints
Similar named colors
Frequently asked
What is the color #04288B?
#04288B is Cobalt, a cool blue color. In RGB it is 4, 40, 139, and in HSL it is 224°, 94%, 28%.
Is #04288B a light or dark color?
#04288B has a relative luminance of 0.034, so it reads as a dark surface. Use light text on top of it for the best contrast.
What colors go well with #04288B?
Its complementary color is #8B6704. For softer combinations, try the analogous or split-complementary harmonies shown above.