Yeah, in the US it's a certain percentage up to a limit, and some people are exempt. Pretty simple in terms of doing payroll

All the complexity is when you file your actual return, and that one would literally be impossible to chart out because there are so many different nooks and crannies that exist that most people don't need to worry about but might so they are out there. I suspect that is also the case in Canada in addition to this payroll calculation nightmare