hmm well I have to ask, are his stools firm or are they like diahrea almost? Is the colour good on them, and are they consistantly the same looking?

If they are not normal, you might want to speak with the vet, but a couple things first.

1.) What food is he on (like everyone else wants to know
2.) Have you recently switched foods... if so..
3.) Did you switch too quickly?
4.) Have you been giving him a lot of wet food or different treats lately, aka is he on a dry kibble diet mostly?

I would take into consideration any possible food allergies to whatever formula you are feeding him, so please tell me if it's like chicken or beef, or a fish or a lamb formula etc.

And I also agree IF it is due to the food you are feeding, try a better higher grade brand. Or if your already feeding him a high grade food, try switching him to a different high grade food.