What leavening agent makes American pancakes fluffy?

Baking powder is the leavening agent that typically makes American pancakes fluffy. It releases carbon dioxide in the batter, creating bubbles that expand as the pancakes cook and give them their thick, light texture.

American pancake batter usually combines flour, eggs, milk and baking powder. The heat of the griddle activates the raising process, while the batter’s structure sets around the gas bubbles. Many recipes also use buttermilk, which adds tanginess and can react with baking soda when both are included.

Baking soda is a common mix-up. It is also a leavening agent, but it needs an acidic ingredient—such as buttermilk, yogurt or lemon juice—to work effectively. Egg whites can add air when whipped, but they are not the standard chemical leavener in ordinary American pancakes. Yeast is used in some specialised pancake traditions, but not usually in everyday breakfast pancakes.

This differs from the classic English pancake, which is thin and generally unleavened. Scotch pancakes are closer to the American style and may use bicarbonate of soda and cream of tartar.