Why use this calculator
Substitution is the point where most home baking goes wrong, because the ratios are rarely one for one and the internet is full of confident guesses. Bicarbonate of soda is roughly three times stronger than baking powder, so swapping them volume for volume gives either a flat bake or a soapy one.
Butter is only about eighty two per cent fat, so replacing a cup of it with a cup of oil adds fat and removes water. Honey brings acid and moisture and browns far faster than sugar, which means less liquid elsewhere and a cooler oven.
This tool applies the published ratio for the exact amount in front of you, offers three alternatives for when the first one is also missing, and says plainly what each swap does to the texture so you can pick the one that suits what you are baking.
How to use it
- Choose the ingredient you need to replace from the list, which covers the ten things home bakers most often run out of.
- Then enter how much the recipe calls for, counted in the unit shown in the result row: whole eggs for eggs, cups for butter, milk, flour and sugar, teaspoons for the raising agents and vanilla, and tablespoons for cornflour.
- The best substitute appears already scaled to that amount, with three alternatives underneath in case the first is also missing from the cupboard.
- Read the notes before you commit, because some swaps also require changing the liquid or the oven temperature elsewhere in the recipe.
What each result means
- Replacing
- The quantity and unit being substituted, restated so you can check it matches the recipe in front of you.
- Best substitute
- The closest match in texture and behaviour, already multiplied out to your amount.
- Alternative 1
- The next best option, useful when the first substitute is also missing or does not suit the bake.
- Alternative 2
- A third option, often better for a specific kind of bake such as a cake rather than a biscuit.
- Alternative 3
- A fourth option, usually the most different in flavour or texture but still workable.
- Works best in
- The kinds of baking this ingredient swap suits, so you can judge whether to try it at all.
- How it changes the bake
- What the substitution does to texture, rise, colour or flavour, and what else to adjust in the recipe.
The formula
Substitution is proportional:
substituteAmount = recipeAmount x publishedRatio
Examples of the ratios applied here: one egg to a quarter cup of apple sauce, one egg to one tablespoon of ground flaxseed plus three tablespoons of water, one teaspoon of baking powder to a quarter teaspoon of bicarbonate of soda plus half a teaspoon of cream of tartar, one teaspoon of bicarbonate of soda to three teaspoons of baking powder, and one cup of sugar to three quarters of a cup of honey with a quarter cup less liquid.
How this number is used in practice
Substitutions work on a sliding scale of forgiveness. A muffin, a loaf cake or a tray bake is loose enough to absorb a swapped fat or a plant milk without complaint. A laminated pastry, a shortbread, a meringue or a caramel is not, because in those the ingredient is the structure rather than a flavour: sugar in meringue is doing the work of holding air, and solid butter in pastry is doing the work of making layers. Match the ambition of the substitution to the fragility of the recipe and most swaps succeed.
The second rule is to change one thing at a time. Each substitution shifts moisture, fat, acidity or lift a little, and the effects compound rather than cancel. Replacing the eggs, the butter and the milk in one go leaves you with a recipe nobody has ever tested, and when it fails there is no way to tell which change caused it.
Change one ingredient, write down what happened, and bake it again. This is also why liquid sweeteners come with instructions to reduce the other liquid and lower the oven: those are not optional extras, they are what makes the swap work.
Worked examples
Replacing 2 eggs in a cake
0.5 cup unsweetened apple sauce, or 6 tbsp aquafaba
Replacing 1 cup of buttermilk for scones
1 cup milk plus 1 tbsp lemon juice, rested 5 minutes
Out of bicarbonate of soda, recipe needs 1 tsp
3 tsp baking powder in its place
When people use it
- Finishing a bake when an ingredient runs out halfway through
- Adapting a recipe for a dairy free, egg free or vegan household
- Baking around a food allergy without hunting through comment sections
- Swapping in a raising agent you have for the one the recipe names
- Reducing the refined sugar in a recipe without wrecking the texture
Tips
- Change one ingredient at a time. Stacked substitutions compound and leave you with nothing to learn from when it fails.
- Egg substitutes hold up to about three eggs in a recipe. Beyond that the structure has nowhere to come from.
- Liquid sweeteners need the other liquid cut and the oven dropped about 15 degrees Celsius, or the outside burns first.
- Bicarbonate of soda is roughly three times stronger than baking powder, so never swap them volume for volume.
- Soured milk needs five to ten minutes to thicken before it behaves like buttermilk. Do not rush it into the bowl.
- Test an unfamiliar substitution on a half batch before committing a birthday cake or a dinner party dessert to it.
What it assumes, and where it stops being accurate
- Ratios are the common published kitchen standards and assume an ordinary domestic recipe rather than a commercial formula.
- Cup based ratios use the same cup throughout, so the substitution scales correctly whichever cup standard you measure with.
- Only one ingredient is being substituted. The ratios do not account for the interaction of two or more swaps at once.
- The bake is a normal cake, biscuit, muffin or quick bread. Pastry, meringue, caramel and enriched doughs are far less tolerant.
- Flavour will shift with most substitutions, so the guidance covers texture and structure rather than promising an identical taste.
Terms used on this page
- Flax egg
- One tablespoon of ground flaxseed mixed with three tablespoons of water and rested until it gels, used in place of one egg.
- Aquafaba
- The liquid drained from a tin of chickpeas, which whips like egg white and replaces eggs in light batters.
- Cream of tartar
- A dry acid that reacts with bicarbonate of soda, which is how home made baking powder works.
- Raising agent
- Baking powder, bicarbonate of soda or yeast, the ingredient that produces gas and lift in a bake.
- Self-raising flour
- Plain flour with baking powder and salt already added, about 2 tsp of powder and half a teaspoon of salt per cup.
Questions people ask
- What can I use instead of an egg in baking?
- A quarter cup of unsweetened apple sauce per egg is the most reliable swap in cakes and muffins. A flax egg made from one tablespoon of ground flaxseed and three tablespoons of water works well in biscuits, and three tablespoons of aquafaba suits lighter batters and can be whipped for meringue style uses.
- How do I make buttermilk at home?
- Add one tablespoon of lemon juice or white vinegar to one cup of milk and leave it to stand for five to ten minutes until it thickens and looks slightly curdled. The acid is what matters, since it reacts with bicarbonate of soda for lift and tenderises the crumb the same way real buttermilk does.
- Can I swap baking powder and bicarbonate of soda?
- Not one for one. Bicarbonate of soda is about three times stronger, so replacing one teaspoon of it needs three teaspoons of baking powder. Going the other way, one teaspoon of baking powder is a quarter teaspoon of bicarbonate of soda plus half a teaspoon of cream of tartar, which supplies the acid.
- Can I replace butter with oil in a cake?
- In cakes, muffins and loaf breads, yes. Use about three quarters of a cup of oil per cup of butter, since butter is roughly eighty two per cent fat and the rest is water, and add a couple of tablespoons of liquid back. Pastry and shortbread need solid fat and do not work with oil.
- How do I use honey instead of sugar?
- Use three quarters of a cup of honey per cup of sugar, cut the other liquid in the recipe by about a quarter cup, and drop the oven around 15 degrees Celsius. Honey is sweeter, wetter and more acidic than sugar, and it browns much faster, so an unadjusted swap burns on the outside.
- Can I make several substitutions in one recipe?
- It is far safer to change one or two at most. Each swap shifts moisture, fat, acidity or lift a little, and the effects compound in ways that are hard to predict. If several ingredients have to change, look for a recipe written that way from the start rather than converting an existing one.
Use this with
Baking Substitution Calculator answers one part of the question. These pick up where it stops: Cups to Grams Converter, Cup Converter, Tablespoon and Teaspoon Converter and Bread Hydration Calculator.
Where these figures come from
This calculation is jurisdiction-neutral arithmetic. No country-specific rules are applied.
- USDA FoodData Central. Gram weights for household measures of common ingredients
- US FDA food labelling and nutrition. Defines the labelling cup as 240 mL, tablespoon 15 mL, teaspoon 5 mL
- Food Standards Australia New Zealand. Australian and New Zealand metric measures and food safety guidance
Baking Substitution Calculator produces an estimate for general information. It is not financial, tax, medical, legal or engineering advice. read the full disclaimer. Spotted a wrong number? Report it and it gets fixed. The form picks up this calculator and the inputs you used.