As of mid-2010 the Canadian and US dollars are nearly the same so the coin is worth about the same in both countries. However Canadian Coins aren't accepted in many US stores except near the border. Also nearly all Canadian 5-cent piece(*) are made of pure nickel or steel which are attracted to a magnet, so they probably won't work in an American vending machine either.
(*) The coin is more often called a 5-cent piece in Canada, although the term "nickel" is used as well.
Chat with our AI personalities
As of late 2012 the 2 currencies are almost equal so it's worth about 5 cents in either country.
You may have difficulty spending a Canadian nickel in the US anywhere except in border areas, though. It may not even work in a US vending machine because the coins are made of very different metals - US nickels are made of a nonmagnetic cupronickel alloy while Canadian nickels are made of plated steel which is strongly attracted to a magnet.
The Canadian and US dollars have been roughly at par for several years so your coin is worth 5 cents in either country, although you may have difficulty getting anyone to accept it in the US.