What's the Difference Between Baking Powder and Baking Soda? (2024)

Baking is a science—and baking powder and baking soda are a big part of it! Both work their magic to create the ideal texture in baked goods, like cakes, muffins and cookies. But have you ever started to bake something and thought: When should I use baking powder vs. baking soda? Do they serve the same purpose? Can I substitute one in place of the other? Do I really need to use both when a recipe calls for them?

Here’s the bottom line: Baking powder and baking soda are both leaveners, but they work in different ways. The two ingredients look very similar due to their white color and powdery texture (even their names are confusingly similar!), but they both bring something special to the table. If you’re out of either, it’s important to make the correct substitution instead of leaving out the leavener entirely. (Otherwise, you might end up with a flat or tasteless treat!) Check out these helpful baking powder substitutes and baking soda substitutes if you’re in a pinch—you might have a great substitute in your kitchen already.

Here’s a helpful tip before you use baking powder or baking soda: Neither lasts forever. Baking powder is usually good for about 12 months and baking soda is typically good for 6 months if stored in a cool, dry place—but like any ingredients, they can go bad sooner. Always check the expiration dates to start. If your leaveners are past their prime or if you’re worried they might not be potent, it’s easy to test them to find out. To test baking powder: Mix ½ teaspoon baking powder with ½ cup hot water, then stir. To test baking soda: Mix ½ teaspoon baking soda with 3 tablespoons distilled white vinegar and stir. Both mixtures should bubble as soon as they get mixed with the liquid.

Keep reading to learn more about baking powder vs. baking soda and when to use one over the other. You’ll never confuse these two baking staples again!

Are baking soda and baking powder the same?

Nope! They may seem similar, but baking powder and baking soda are not the same. Both are leavening agents, but they act differently in recipes—see below. Knowing the difference between the two ingredients is important if you’re baking. Due to their different chemical compositions, each plays a different part in making a recipe successful.

What is baking powder?

Baking powder is actually baking soda mixed with a dry acid. When baking powder comes in contact with a liquid, it releases carbon dioxide bubbles, which cause baked goods to rise. So all it needs is a little water or other non-acidic liquid in order to work. Most baking powder that you buy at the store is "double-acting," which means it's activated once when it hits liquid and again when it's heated.

What is baking soda?

Unlike baking powder, baking soda doesn’t contain an acid. This means that it needs something acidic, like lemon juice, buttermilk, or vinegar, in order to work. That chemical reaction is key to adding the lift you want to achieve. Baking soda is much stronger than baking powder (three or four times stronger!), so you usually don’t need as much. Too much baking soda can make food taste metallic or soapy, so be sure to measure correctly.

Why do some recipes call for baking soda and baking powder?

If your recipe calls for both baking powder and baking soda, it’s probably because there is an acid in the recipe to activate the baking soda, but that chemical reaction alone isn’t enough to give the dish the desired volume. (Remember, too much baking soda will affect the flavor.) Adding baking powder provides balance and is done to create the perfect lift.

Can you use baking soda in place of baking powder?

The best baking powder substitute is a mix of baking soda and cream of tartar. The cream of tartar adds acidity to the baking soda—it's basically homemade baking powder. Use this in a pinch, or make a larger batch and store it in an airtight container for baking powder emergencies. To make 1 tablespoon baking powder, mix 2 teaspoons cream of tartar with 1 teaspoon baking soda (add 1 teaspoon cornstarch if you're making a big batch—it prevents the mixture from caking, but it's not necessary).

Can you use baking powder in place of baking soda?

Since baking powder contains baking soda already, you can usually use about 1 teaspoon of baking powder for every 1/4 teaspoon of baking soda called for in the recipe. And if you want to get super technical, once you make that swap, consider replacing any acidic liquids in the recipe with non-acidic liquids to prevent the extra acid found in the baking powder from causing a separate reaction.

Is there a trick to remembering the difference between baking powder and baking soda?

Still not sure you’ll remember when to use baking powder vs. baking soda? Here’s an easy way to tell the two ingredients apart: Baking powder = power. It can lift baked goods up since it already contains baking soda so it doesn't need anything else. Baking soda = solo. It’s a single ingredient that needs an acid to help it do the heavy lifting.