Blog

If you’ve ever stood in the baking aisle staring at the difference between baking powder and baking soda, you’re not alone. They’re both white powders, both used in baking… but they’re not interchangeable, and using the wrong one can ruin a recipe.

In this guide, you’ll learn:

• What baking soda and baking powder actually are
• How they work in your desserts
• When to use one, the other, or both
• How to test if yours is still fresh

Let’s settle this baking mystery once and for all.

What Is Baking Soda?

Baking soda, also known as sodium bicarbonate, is a pure alkaline compound. When combined with an acid and a liquid, it creates carbon dioxide gas, which helps batter or dough rise.

Common acids used in baking:

• Buttermilk
• Yogurt
• Vinegar
• Lemon juice
• Brown sugar (contains molasses)
• Cream of tartar

How it works:
Baking soda reacts immediately when it comes into contact with acid + liquid. That’s why baked goods using only baking soda should be baked right away.

When to use it:
Use baking soda when your recipe includes an acidic ingredient and you need a quick rise.

What Is Baking Powder?

Baking powder is a combination of baking soda + acid (usually cream of tartar) + cornstarch to keep it dry. Most store-bought baking powders are double-acting, meaning they release gas twice:

1. Once when mixed with liquid
2. Again when exposed to oven heat

How it works:
Because it already contains acid, baking powder doesn’t need an acidic ingredient in your recipe. It’s essentially a “self-contained leavening agent.”

When to use it:
Use baking powder when your recipe does not contain another acid or when you want a longer window before baking.

Why Do Some Recipes Use Both?

Some recipes call for both baking soda and baking powder to:

• Balance the pH (especially if the acidic ingredient isn’t strong enough alone)
• Control browning and flavor
• Extend the leavening reaction

Can I Substitute One for the Other?

Short answer: Not directly.

If you must substitute:

To replace baking powder with baking soda:
Use:

• ¼ tsp baking soda + ½ tsp cream of tartar = 1 tsp baking powder
  (Only works if you have cream of tartar.)

To replace baking soda with baking powder:
Use:

• 3x the amount of baking powder
  (But be aware it may affect taste and texture.)

That said, it’s best to stick with what your recipe calls for!

How to Test Freshness

Both of these can lose potency over time, especially if stored in a humid kitchen.

Test baking soda:
Add a splash of vinegar to ¼ tsp of baking soda.
If it bubbles vigorously, it’s still good.

Test baking powder:
Add a few tablespoons of hot water to ½ tsp of baking powder.
If it fizzes, it’s still active.

📌 Final Thoughts

Baking soda and baking powder might look alike, but they serve very different roles in baking. Knowing when and how to use them is a game-changer—your cakes will rise better, your cookies will brown just right, and you’ll avoid those dreaded baking fails.