Cobalt
#00288F · Cobalt
#00288F is Cobalt, a cool blue color. It has an RGB value of 0, 40, 143 and a relative luminance of 0.035, making it a dark surface.
Temperature
❄ Cool
Hue family
blue
Luminance
0.04
Conversions
HEX
RGB
HSL
HSV
CMYK
OKLCHPro
Contrast & accessibility
On white
The quick fox
12.35:1
AA normal✓
AA large✓
AAA normal✓
On black
The quick fox
1.70:1
AA normal✕
AA large✕
AAA normal✕
Color harmonies
Complementary
Split-complementary
Shades & tints
Similar named colors
Frequently asked
What is the color #00288F?
#00288F is Cobalt, a cool blue color. In RGB it is 0, 40, 143, and in HSL it is 223°, 100%, 28%.
Is #00288F a light or dark color?
#00288F has a relative luminance of 0.035, so it reads as a dark surface. Use light text on top of it for the best contrast.
What colors go well with #00288F?
Its complementary color is #8F6600. For softer combinations, try the analogous or split-complementary harmonies shown above.