Baking Powder vs Baking Soda: Amounts and Substitutes
Baking soda and baking powder both make baked goods rise, and they sit side by side in the cupboard. But they are not the same, and using one in place of the other without adjusting can leave you with a flat cake or a soapy taste.
What’s the difference?
- Baking soda is pure sodium bicarbonate. It only works when it meets an acid in the recipe, such as buttermilk, yogurt, brown sugar, honey, lemon juice, vinegar or natural cocoa. It is about three to four times stronger than baking powder.
- Baking powder is baking soda that already has a dry acid (and some starch) mixed in. Add any liquid and it starts working. Most baking powder is “double-acting”: it bubbles a little when wet, and again in the heat of the oven.
Many recipes use both: baking soda to balance an acidic ingredient and help browning, and baking powder for extra lift.
How much to use
| Usual amount per 1 cup flour | 1 teaspoon weighs | |
|---|---|---|
| Baking powder | 1 to 1 1/4 tsp | about 4 g |
| Baking soda | 1/4 tsp (with an acidic ingredient) | about 6 g |
Spoon weights are from our baking powder and baking soda pages. More spoon weights: how many grams in a tablespoon.
Substitute baking powder for baking soda
If you’re out of baking soda, use about 3 times as much baking powder: 1/2 tsp baking soda → 1 1/2 tsp baking powder. It works, but the result may be slightly less brown and a little more cakey, and if the recipe is very acidic it may taste a touch tangier.
Substitute baking soda for baking powder
Make your own baking powder: for every 1 tsp baking powder, mix 1/4 tsp baking soda + 1/2 tsp cream of tartar. Use it straight away, because homemade powder is single-acting and starts reacting as soon as it gets wet. Get the batter into the oven quickly.
No cream of tartar? If the recipe has an acidic liquid like buttermilk or yogurt, you can use 1/4 tsp baking soda per teaspoon of baking powder and let that acid do the work.
Signs you used the wrong amount
- Too much baking soda: soapy or metallic taste, dark color, coarse crumb.
- Too much baking powder: bitter taste, a cake that rises fast and then sinks.
- Too little of either: dense, heavy and flat.
Is yours still working? Two quick tests
- Baking powder: stir 1/2 tsp into a few tablespoons of hot water. It should fizz right away.
- Baking soda: add 1/4 tsp to a splash of vinegar. It should bubble hard.
No fizz means it has lost its strength, so replace it. Keep both tightly closed in a dry cupboard; humidity is what kills them.
Measuring tips
Use level measuring spoons and scrape off the excess. Small errors matter here, because these ingredients are used in tiny amounts. Whisk them into the flour well, so you don’t bite into a bitter pocket. Converting a whole recipe? Paste it into the recipe converter.
Was this page helpful?
Thanks, we read every report.