Baking soda vs. baking powder
Beginner Kitchen science
Both release carbon dioxide gas to lift batters, but baking soda needs an acid in the recipe while baking powder brings its own.
Written with AI help from the sources listed, and published by Cory. Spot a mistake? Tell us and we'll fix it.
How do you do it?
- Use baking soda with acidic ingredients like buttermilk, yogurt, brown sugar, molasses, honey or natural cocoa.
- As a rough guide, use about 1 teaspoon baking powder or 1/4 teaspoon baking soda per cup of flour.
- Test old leaveners: baking powder should fizz in hot water, baking soda in a splash of vinegar.
- Substitute 1 teaspoon baking powder with 1/4 teaspoon baking soda plus 1/2 teaspoon cream of tartar if you run out.
Why does it work?
Baking soda is sodium bicarbonate, a base. When it dissolves and meets an acid it releases carbon dioxide right away, so batters made with only soda should go into the oven promptly. Any soda without enough acid to react with leaves a soapy, metallic taste and extra browning. Baking powder is baking soda premixed with dry acids and starch. Most supermarket powder is double-acting: one acid reacts when it gets wet, and a second reacts only with oven heat, giving a second lift. The bubbles do not create holes on their own; they expand air pockets beaten into the batter.
What are the common mistakes?
- Using soda where powder is called for — flat, soapy-tasting, too-dark baked goods.
- Keeping leavener for years — it loses strength and cakes come out dense.
Still stuck? Watch someone do it on YouTube.
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