What's the Difference Between Baking Soda and Baking Powder?

If you open just about any pantry, you'll find two of the most common leavening agents used in household baking: baking soda and baking powder.

While they may look like twins, baking soda and baking powder each have unique properties that any budding baker needs to be aware of.

To get the facts, I spoke with two leading dietitians: Amber Pankonin, a culinary instructor at Great Plains Culinary Institute in Lincoln, NE and registered dietitian and personal chef at Stirlist.com, and Wendy Jo Peterson, MS, RDN, a global culinary instructor and author of eight books, including her latest Bread Making Cookbook For Dummies.

What is Baking Soda?

According to Pankonin, baking soda (aka sodium bicarbonate) is an alkaline compound that releases carbon dioxide when both an acid and moisture (like buttermilk or sour cream) are present. For the reaction to take place, heat is not needed but the product should be immediately placed in the oven for baking so that the carbon dioxide doesn't escape from the batter or dough. 

What is Baking Powder?

Baking powder, on the other hand, contains sodium bicarbonate, an acid, like cream of tartar or sodium aluminum sulfate, and a starch, like corn starch, to prevent lumping. When using baking powder, the only thing needed for the leavening action to occur is moisture (because baking powder already contains an acid).

There are two different types of baking powder: single-acting and double-acting baking powder.

Single-acting baking powder produces a small amount of gas when moisture is applied, like the wet ingredients in a recipe, whereas double-acting baking powder produces the first release of gas with the moisture application and another release of gas when heat is applied, such as the heat from the oven.

Nutrition Facts: Baking Soda

Baking soda contains sodium bicarbonate as the sole ingredient. Given this, baking soda itself has no other nutritional value other than providing sodium.

The following information is provided by the USDA for 1 teaspoon (4.6 grams) of baking soda.

Nutrition Facts: Baking Powder

Most baking powder sold in the United States is double-acting, meaning it reacts twice during the baking process (first when exposed to the wet ingredients in a recipe, then again when exposed to the heat).

Double-acting baking powder has a few more ingredients than baking soda, including baking soda (or sodium bicarbonate) itself in addition to corn starch, sodium aluminum sulfate, and monocalcium phosphate.

Due to these additions, baking powder has a unique nutrient profile in comparison to baking soda. The following information is provided by the USDA for 1 teaspoon (4.6 grams) of baking powder, double-acting, straight phosphate.

Benefits of Baking Soda

Doubles As a Household Cleaner

Consult Google and you'll find an array of do-it-yourself ideas to use baking soda as a household cleaner, in addition to acting as a pharmaceutical to treat digestive issues such as heartburn.

According to Peterson, "baking soda is great for cleaning, from boosting laundry detergent or stain remover to scrubbing ovens." She suggests mixing baking soda and vinegar to create a powerful cleaning paste.

May Extinguish Grease Fires

Peterson shares that baking soda can also help with grease fires (while baking powder cannot). She advises proceeding with caution and double-checking which ingredient you're using since, "If you put baking powder on a grease fire it will create a POW (pow-powder) explosion. It's best to know the difference in this case."

Alleviates Heartburn

According to the US National Library of Medicine, the pharmaceutical use of baking soda, also known as citrocarbonate or brand names such as Alza-Seltzer® or Zegerid®, is common to help alleviate symptoms related to heartburn.

However, because sodium bicarbonate contains large amounts of sodium, it's recommended to work with a physician before including these medicines for your own dietary needs, especially if you are on a salt-restricted diet.

May Influence Athletic Performance

While past research demonstrated the potential benefit of including baking soda as an ergogenic aid to improve athletic performance, more recent reviews suggest this may not be the case for every individual.

Before incorporating baking soda into your training regimen, take a closer look at your own personal training program and consider speaking with a trained sports dietitian to identify the supplements that may be warranted for your particular needs.

Benefits of Baking Powder

While baking soda has a plethora of uses beyond baking, baking powder does not. Since baking powder consists of other ingredients alongside sodium bicarbonate, it will not perform the same if swapped for baking powder in household chores like cleaning or do-it-yourself medical uses such as managing heartburn or improving athletic performance.

Which to Use: Baking Soda, Baking Powder, or Both?

For Recipes With an Acidic Ingredient: Baking Soda

Baking soda is often used in recipes that already include an acidic ingredient (like lemon or buttermilk). This acidic ingredient will release the baking soda's carbon dioxide, giving the recipe its lift. But, since the carbon dioxide is released when combined with the acidic moisture, you'll want to quickly move the recipe into the oven to ensure the proper leavening takes place.

For Recipes Without an Acidic Ingredient: Baking Soda

Baking powder is used in recipes that don't include an acidic ingredient, as it already contains its own acidic component. Most US baking powders are double-acting, so you can let recipes with baking powder sit a little longer since it will produce a second reaction when placed under heat.

For Recipes That Require Leavening: Both

According to Pankonin, "the reason why some recipes might call for both is because baking soda will release carbon dioxide based on the acid that is used in the recipe. This might not provide enough leavening, which is why baking powder may also be needed."

She does advise that too much of either can make the final product taste bitter or cause discoloration in baked goods. Proceed with precision when adding both baking soda and baking powder into your recipes.

Substitutions and Swaps

Both Pankonin and Peterson agree that you should not substitute baking soda and baking powder one-for-one in baking since they function differently.

They do agree, however, that baking powder would be an acceptable substitute for baking soda because it already contains sodium bicarbonate. The general rule is that if a recipe calls for one teaspoon of baking soda, use three teaspoons of baking powder.

However, Pankonin shares, "you'll also want to consider what the recipe calls for in terms of salt. Since baking powder contains salt, you might want to reduce the amount of salt in the recipe."

If you need a substitute for baking powder, Peterson suggests mixing together baking soda and cream of tarter to mimic the effects of the ingredient. She also shares that you can mix an acidic liquid (such as yogurt, buttermilk, or club soda) with a touch of baking soda if you do not have cream of tartar.

If you are out of both baking soda and baking powder, Peterson suggests trying whipped egg whites as a substitute to provide the lift a leavening agent will add to baked goods. However, it's recommended to give this a try before banking on it for a final recipe, as the end result may be different than you'd hoped.

A Word From Verywell

While baking soda and baking powder both serve as leavening agents in the kitchen, baking soda reigns superior for multi-use purposes.

While you can certainly experiment with baking soda as a cleaning agent in your house, we advise proceeding with caution and consulting a healthcare professional before implementing baking soda as a remedy for any serious medical condition.