They have different uses.

Baking powder is a key leavening agent in everything from pancakes to cakes, helping baked goods, breakfast treats, and more ...

Baking soda and baking powder are both used in baking, but they are not interchangeable.

Q: It seems as if every time a recipe calls for baking powder, I never get the rise I expect. I have made cakes and pound cakes that flopped with fresh-from-the-market baking powder, and they have ...