For one egg in baking, use 1/4 cup liquid egg substitute, or mix 1 tablespoon ground flaxseed with 3 tablespoons water. Applesauce (1/4 cup) works well in muffins and quick breads.
Ratios from university extension services and King Arthur Baking. Checked .
Eggs (in baking) substitutes, best first
- For 1 large egg1/4 cup liquid egg substituteBest for: any baking
Nebraska, UC, Colorado State.
- For 1 large egg1 Tbsp ground flaxseed + 3 Tbsp waterBest for: muffins, cookies, quick breads
University of Illinois Extension.
- For 1 large egg1/4 cup applesauce or 1 mashed bananaBest for: muffins, quick breads, brownies
University of Illinois Extension; adds moisture and flavor.
- For 1 large egg2 Tbsp mayonnaiseBest for: cake batter only
Nebraska, UC.
- For 1 large egg1/2 tsp baking powder + 1 Tbsp vinegar + 1 Tbsp liquidBest for: baking only
Nebraska, Colorado State.
- For 1 large egg2 egg yolks + 1 Tbsp waterBest for: cookies
NMSU, Mississippi State.
Why the swaps work
Eggs bind, add moisture and structure, and help leaven; Purdue rates one egg's lift at about 1/2 tsp baking powder. Swaps cover some roles better than others.
Questions people ask
What's the best egg substitute for cake?
Liquid egg substitute (1/4 cup per egg) is closest; 2 Tbsp mayonnaise also works in cake batter.
How do I make a flax egg?
Mix 1 Tbsp ground flaxseed with 3 Tbsp water (University of Illinois).
Can I replace eggs in cookies with yolks?
Yes: 2 yolks plus 1 Tbsp water per whole egg.
Sources
- Cooking Substitution Guide (University of Illinois Extension)
- Ingredient Substitutions (Nebraska Extension, UNL)
- Ingredient Substitution (UC Cooperative Extension, UC ANR)
- Ingredient Substitutions, Fact Sheet 9.329 (Colorado State University Extension)
- In a Pinch: Ingredient Substitution, Guide E-131 (New Mexico State University Extension)
- Ingredient Substitutions and Equivalents, P1690 (Mississippi State University Extension)
- Substitutions and Equivalents in Food Ingredients, CFS-145-W (Purdue Extension)