For 1 teaspoon baking powder, mix 1/4 teaspoon baking soda with 1/2 teaspoon cream of tartar. Combine it right before using and bake promptly, because this blend starts reacting as soon as it gets wet.
Ratios from university extension services and King Arthur Baking. Checked .
Baking powder substitutes, best first
- For 1 tsp baking powder1/4 tsp baking soda + 1/2 tsp cream of tartar (+ 1/4 tsp cornstarch if storing)Best for: cakes, biscuits, quick breads
King Arthur and Iowa State give this ratio; Nebraska, UC and Utah State list 5/8 tsp cream of tartar, and Mississippi State/Purdue 1/3 tsp soda + 1/2 tsp cream of tartar. Mix just before using.
- For 1 tsp baking powder1/4 tsp baking soda + 1/2 cup buttermilk, sour milk or yogurtBest for: recipes that already contain milk
Cut the recipe's other liquid by 1/2 cup (Mississippi State, Purdue, NMSU).
- For 1 tsp baking powder1/4 tsp baking soda + 1/2 Tbsp vinegar or lemon juice, plus sweet milk to make 1/2 cupBest for: pancakes, muffins
Reduce other liquid by 1/2 cup (Utah State, Purdue).
- For 1 tsp baking powder1/4 tsp baking soda + 1/4 to 1/2 cup molassesBest for: gingerbread and spice cakes
Molasses adds sweetness and color; adjust sugar and liquid (Utah State, Purdue).
What not to use
Baking soda by itself in a recipe with no acid: soda only releases gas when it meets an acid, so the bake rises poorly. Don't swap soda for powder 1:1 either.
Why the swaps work
Baking powder is baking soda already mixed with a dry acid (and starch). Double-acting powder makes gas once when wet and again in the oven's heat.
Questions people ask
Can I use baking soda instead of baking powder?
Only with an acid. Use 1/4 tsp soda plus 1/2 tsp cream of tartar, or 1/4 tsp soda with 1/2 cup buttermilk (and 1/2 cup less other liquid), per 1 tsp powder.
How do I test if baking powder is still good?
Stir about a teaspoon into a tablespoon of water; fizzing means it's active (King Arthur).
Is homemade baking powder double-acting?
No. A soda-plus-acid mix reacts right away, so get the batter into the oven quickly.
What can I use instead of baking powder?
For 1 teaspoon baking powder, mix 1/4 teaspoon baking soda with 1/2 teaspoon cream of tartar. Combine it right before using and bake promptly, because this blend starts reacting as soon as it gets wet.
What can I substitute for baking powder?
For 1 teaspoon baking powder, mix 1/4 teaspoon baking soda with 1/2 teaspoon cream of tartar. Combine it right before using and bake promptly, because this blend starts reacting as soon as it gets wet.
Sources
- The difference between baking soda and baking powder, plus substitutions (King Arthur Baking)
- Substitutions for Common Foods (Iowa State University Extension AnswerLine)
- Ingredient Substitutions (Nebraska Extension, UNL)
- Ingredient Substitution, FN 255 (Utah State University Extension)
- Ingredient Substitutions and Equivalents, P1690 (Mississippi State University Extension)
- Substitutions and Equivalents in Food Ingredients, CFS-145-W (Purdue Extension)
- In a Pinch: Ingredient Substitution, Guide E-131 (New Mexico State University Extension)