Kittens are generally ready to leave their mother and start eating regular food at about eight weeks of age. Until this age, kittens get all the nutrition they need from their mother's milk, although they may start tasting their mother's food at four weeks old.
Between four and eight weeks of age, kittens slowly begin transitioning to solid food. Once kittens are weaned, they can be fed a steady diet of kitten food. They should be given as much food as they want until they are one year old. Unlike other pets, kittens will usually not overeat, so food can be left for them at all times.