What can You Use Instead of Baking Powder?

One teaspoon of baking powder can be replaced with 1/ 2 teaspoon cream of tartar plus 1/4 teaspoon baking soda. You can also find calcium carbonate, if you are trying to make a sodium free baking powder, at your local health food store. Use it any recipe that calls for baking soda or in homemade baking powder recipes that require baking soda.