Baking soda vs. baking powder: What’s the difference, and how to sub one for the other

We’ve all been there: You’re almost done making your favorite cookie dough and realize you’re fresh out of baking soda. What’s a home chef to do?

Create your own substitute, that’s what! While baking soda and baking powder are different ingredients, you can use one or the other in your recipes — as long as you make some adjustments. Read on to learn more about these pantry staples, and what to do when you’re out of one or the other. 

What is baking soda and what is baking powder?

Baking Soda and baking powder are both leavening agents containing sodium bicarbonate. When mixed with other ingredients in recipes for baked goods, they create air bubbles — made of carbon dioxide — which causes dough or batter to rise, creating a lighter texture. Think fluffy pancakes, rather than flat hockey pucks. 

Baking Soda is pure Sodium Bicarbonate, also referred to as Bicarbonate of Soda. It needs to be mixed with an acid, like yogurt, lemon juice, buttermilk, molasses or brown sugar, in order to create air bubbles — kind of like a science fair volcano experiment, but with muffins. Baking soda also neutralizes acidity and helps make baked goods tender and brown. 

Baking Powder, on the other hand, is a mixture of baking soda along with acidic salts, like cream of tartar. And it can also contain starch. Because baking powder already contains sodium bicarbonate and an acid, it only needs moisture to create air bubbles. 

Most baking powder you find today is double acting baking powder, which means some of the air bubbles are created when moisture is added, and more bubbles are created when heat is applied. This ensures maximum fluffiness once your baked goods enter the oven. 

How to substitute baking soda in a recipe

Even though baking powder and baking soda have similar functions in cooking and baking, they can’t be used interchangeably — at least not without making some adjustments first.  

To use baking powder in place of baking soda, replace it with three times the amount of baking powder. So, if your recipe calls for a half-teaspoon of baking soda, use three half-teaspoons (1.5 tsp) of baking powder. 

Here’s a handy conversion chart to help:

How to substitute baking powder in a recipe

To substitute baking powder in a recipe, you’ll need to add in baking soda along with an acid. Since baking soda is much stronger than baking powder, you’ll want to use a quarter of the amount in your recipe. 

Here are some simple conversions, courtesy of Arm & Hammer, depending on which acid you have on hand. 

• 1 tsp. baking powder = ¼ tsp. baking soda plus ½ tsp. cream of tartar (1 part baking soda to 2 parts cream of tartar).

• 1 tsp. baking powder = ¼ tsp. of baking soda plus 1 tsp. of lemon juice or white vinegar (1 tsp. vinegar or lemon juice for every ½ tsp. cream of tartar)

• 1 teaspoon baking soda = 3 teaspoons baking powder.

Tips for baking with baking soda and baking powder

Ready to rise? Here are a few tips for perfectly-leavened baked goods.

Test your baking powder before you use it

Baking powder does go bad, which can ruin your baked goods. To test if yours is still good, mix 1 teaspoon baking powder with 1/4 cup hot water—if it bubbles up vigorously, it’s still good! 

Keeping it in a cool, dry place will help maximize its shelf life. 

Mixed your leavener into your dry ingredients

It’s important to ensure your baking soda or baking powder is evenly distributed throughout your dough or batter — otherwise, your goodies will rise too much in some places and not enough in others. Mix it into the dry ingredients before adding the wet ingredients, since these will activate the leavener. 

DIY your own buttermilk if you need it

Buttermilk is a common ingredient used to activate baking soda — but you may not always have it on hand. To make your own buttermilk, simply add a Tablespoon of vinegar to a cup of milk, then let it sit for 5 minutes. Then, you’re ready to whip up the Classic Buttermilk Waffles of your dreams.