Here You can set color in RGB color model and watch at complimentary colors at bottom of the page or just click random color.
Basic color:
#0c54f6; rgb(12,84,246); hsl(221,85%,51%);
black
black
white
white
Complementary colors:
Analogous harmony (H+30):
#4118ec; rgb(65,24,236); hsl(251,85%,51%);
black
black
white
white
Analogous harmony (H-30):
#18c3ec; rgb(24,195,236); hsl(191,85%,51%);
black
black
white
white
Triadic harmony (H+120):
#ec1858; rgb(236,24,88); hsl(341,85%,51%);
black
black
white
white
Triadic harmony (H-120):
#5aec18; rgb(90,236,24); hsl(101,85%,51%);
black
black
white
white
Split complements harmony (H+150):
#ec3f18; rgb(236,63,24); hsl(11,85%,51%);
black
black
white
white
Split complements harmony (H-150):
#c5ec18; rgb(197,236,24); hsl(71,85%,51%);
black
black
white
white
Complement harmony (H+180):
#eca918; rgb(236,169,24); hsl(41,85%,51%);
black
black
white
white
Monochromatic harmony (S+30):
#0552ff; rgb(5,82,255); hsl(221,100%,51%);
black
black
white
white
Monochromatic harmony (S-30):
#3d67c7; rgb(61,103,199); hsl(221,55%,51%);
black
black
white
white
Monochromatic harmony (L+10):
#477bf0; rgb(71,123,240); hsl(221,85%,61%);
black
black
white
white
Monochromatic harmony (L-10):
#1046c1; rgb(16,70,193); hsl(221,85%,41%);
black
black
white
white