Cobalt
#3F457D · Cobalt
#3F457D is Cobalt, a cool blue color. It has an RGB value of 63, 69, 125 and a relative luminance of 0.068, making it a dark surface.
Temperature
❄ Cool
Hue family
blue
Luminance
0.07
Conversions
HEX
RGB
HSL
HSV
CMYK
OKLCHPro
Contrast & accessibility
On white
The quick fox
8.90:1
AA normal✓
AA large✓
AAA normal✓
On black
The quick fox
2.36:1
AA normal✕
AA large✕
AAA normal✕
Color harmonies
Complementary
Split-complementary
Shades & tints
Similar named colors
Frequently asked
What is the color #3F457D?
#3F457D is Cobalt, a cool blue color. In RGB it is 63, 69, 125, and in HSL it is 234°, 33%, 37%.
Is #3F457D a light or dark color?
#3F457D has a relative luminance of 0.068, so it reads as a dark surface. Use light text on top of it for the best contrast.
What colors go well with #3F457D?
Its complementary color is #7D773F. For softer combinations, try the analogous or split-complementary harmonies shown above.