Two weeks is typical for most jobs in North America.
And it's not required, it's a courtesy. In most cases you can quit on the spot if you really feel like it.
I said "two weeks" on Quora, and some Europeans (Dutch, I think) corrected me and said that 3 months was standard there.
The Dutch don’t have to worry about being fired on a whim
How much notice do they have to give you when they're letting you go?
None. Some walk you out and lock the door immediately.
In my case, they have to give 3 months notice as well. That's what is in the contract. I'm not sure how that would work in practise. I guess they can fire effective immediately but I can't quit effective immediately