How do I convert angles to radians

I know how to convert angles from 0-180 from degrees to radians (pi/2, pi... etc) but I do not know how to convert angles bigger than 180. Examples are 225 degrees, 450 degrees and -225 degrees. Can someone explain how I can convert them?

x * pi/180

x = value in degrees

pi/2 = 90 degrees

pi = 180

2 pi = 360

add subtract appropriately then solve

ie. 450 = 360 + 90 or 2pi + p/2 = 5/2pi

in 360 deg there are 2 pi radians so to convert an angle in degrees to radians
multiply by 2 pi/360 or pi / 180