While these two ingredients have a lot in common, they are not the same. Both are used in baking and help create the chemical reaction that makes bread and cake rise. The difference is, baking powder is made of baking soda but also includes a powdered acid—often cream of tartar—mixed right in. This means that all baking powder needs is moisture for a reaction to occur, no added acid necessary, unlike baking soda.

So why use baking soda at all? The answer is that recipes vary widely in acidity levels and flavoring. And to complicate matters, some recipes call for both baking soda and baking powder! These recipes usually contain some acidic ingredient, such as berries for example, but the carbon dioxide created when the baking soda reacts with the acid isn’t enough to leaven (meaning rise) the amount of batter. That’s where baking powder is very useful, to add that necessary extra lift.