How to Test Baking Soda and Baking Powder to See If They’re Expired

When your pancakes come out too flat or your cake doesn't rise, your leavener might have lost its oomph. Here's how to do a baking powder and baking soda test.

If your favorite baking recipes suddenly stop turning out well, don’t panic! There may be a simple answer—your leavener may be expired. (Here’s the difference between baking soda and powder.)

First things first: check the expiration date. The shelf life for an open container of baking soda or baking powder is about 6 months, but here’s how to test for freshness to be sure:

How to Do a Baking Powder Test

Place 1 teaspoon baking powder in a cup and add 1/3 cup hot tap water. If it starts to bubble, it’s good to go. If not, add it to your grocery list.

How to Do a Baking Soda Test

Place 1/4 teaspoon baking soda in a cup and add 2 teaspoons vinegar. Just like baking powder, if baking soda doesn’t bubble, it’s old and should be replaced.

If you’re left without baking soda or baking powder, check out our handy list of baking substitutions.