There are many situations where you may need to scale and resize a recipe. 

Scenarios:

• You want to make your favourite recipe for a larger group.
• You found a recipe designed for many servings, but you just want two.
• You have some leftover egg whites and want to use all of it before it expires.
• You need exactly 400 grams of mousse to fill a mould.
• You have a recipe for a large mould or cake tin, but you only have a small one.

Doing these calculations can sometimes be complex, especially when you want to preserve the exact proportions for a precise recipe.

Looking for a recipe scaler tool or a recipe resizing calculator? We made a mobile app: Recipe Resizer, to help you scale any recipe so that you don't have to bother with any of the complex and tedious math.

Can any recipe be Scaled up or down?

Any recipe can be scaled up or down successfully, provided they are accurate and precise. Scaling a recipe is about keeping the same proportions as the original. Therefore, more precise a recipe is, the less deviation there will be when the recipe is scaled. 

When scaling a recipe, there are few things you need to watch out for.

Scaling Volumetric recipes

Recipes that contain volumetric measurements such as cups, tablespoons, teaspoons, gallons, litres and milliliters or unit measurements like the number of eggs or gelatin sheets are susceptible to inaccurate proportions after they are scaled. This is because volumetric measurements can be imprecise. Precision in volumetric recipes can be affected by different sized measurement vessel sizes (for example, I have two different varieties of tablespoons measurements from the same store, but they are different sizes!), different sized ingredients (a cup of smaller hazelnuts will have a different weight to a cup of large hazelnuts) and packing density (tightly vs loosely packed). When an imprecise volumetric recipe is scaled, the differences are amplified.

Fortunately, most of the time this difference won’t matter, however, a little extra flour here or there could mean the difference between a cake that is moist or dry or choux puffs that are light or dense. The alternative to volumetric measurements are weighted measurements which are consistent and will allow for precise recipe scaling.

Method Adjustments

Scaling a recipe can also require changing the method. Just because the ingredient proportions are the same, doesn’t mean that the same method will work. A larger recipe will take longer to bake and heat (they also retain heat for longer) and conversely, a smaller recipe will heat more quickly and may overcook if you don’t adjust the time or keep a close watch. The method can’t be adjusted linearly. For example, if we’re making 2 times the recipe, we can’t just double the duration of baking or double the temperature. When a recipe is scaled, you will need to adjust, use your instincts and/or experiment with trial and error.

Another point to note is that some recipes require an amount to be within a certain range to be practical. For example, it is easier to emulsify a ganache without introducing air bubbles when there is enough ganache for the immersion blender to be completely submerged. 

How to Scale a Recipe by a Multiplier

Scaling a recipe by a multiplier is one of the most common ways to scale a recipe. Sometimes we want to double or triple a recipe if we want to make more of it. Other times we want to cut down in half or in quarters. The way to scale a recipe by a multiplier is to multiply each ingredient by that multiplier.

Sometimes you may be looking for how to quarter or halve a recipe. To do that you will just need to divide every ingredient by the divider. So if you're looking to quarter a recipe, then divide every ingredient amount by 4.

Formula

For each ingredient: original ingredient amount × multiplier

If dividing: For each ingredient: original ingredient amount ÷ divider

Example Scenario

Kirsten has a mousse recipe but wants to make a lot more for a gathering, so she decides to make 3 times as much.

Original Dark Chocolate Mousse Recipe

• 300 g Heavy cream
• 60 g Whole milk
• 140 g Dark chocolate pieces

She multiplies each ingredient by 3.

Desired Dark Chocolate Mousse Recipe

• 900 g Heavy cream (300 × 3)
• 180 g Whole milk (60 × 3)
• 420 g Dark chocolate pieces (140 × 3)

The Foundational way to Scale a Recipe

Scaling a recipe is about maintaining the same proportions of ingredients. We can do that by multiplying each ingredient by the same number (i.e, a multiplier). All the other scenarios of scaling a recipe use the same method of multiplying all ingredients by the same number, but have different ways to calculate that multiplier to achieve the desired result.

How to Scale a Recipe by Number of Servings or Portion Size

The way to scale a recipe by number of servings is to multiply the original amount by the desired serving size and then divide by the original serving size.

We are essentially doing the same thing as scaling a recipe by a multiplier. The multiplier is determined by the desired serving size divided by the original serving size. If we have an original serving size of 10 and a desired serving size of 16 then our multiplier will be 16 divided by 10 which is 1.6. I.e., The desired serving size of 16 is 1.6 times larger than the original serving size.

Formula

For each ingredient: original ingredient amount × desired serving size ÷ original serving size

Example

Adriano is making macarons as Christmas presents for 10 of his friends. He wants to give them a box of 5 each, a total of 50 macarons. Adriano has a recipe for 30 macarons.

Macaron Shell Recipe for 30 Macarons

• 150g almond meal
• 150g icing sugar
• 110g egg white
• 150g caster sugar
• 50g water

Adriano divides the desired number of servings, 50, by the original number of servings, 30 and multiplies the result for each ingredient.

Macaron Shell Recipe for 50 Macarons

• 250g almond meal (150 × 50 ÷ 30)
• 250g icing sugar (150 × 50 ÷ 30)
• 183g egg white (110 × 50 ÷ 30)
• 250g caster sugar (150 × 50 ÷ 30)
• 83g water (50 × 50 ÷ 30)

How to Scale a Recipe to Have a Specific Amount of an Ingredient

When looking for how to scale baking recipes, a common need is to scale a recipe to have a specific amount of an ingredient. This is useful if you want to use up the remainder of an ingredient, or you only have a specific amount available. For example, all eggs are different sizes so when you crack a few eggs, you usually won't have the exact amount the recipe calls for. This is when it's useful to scale a recipe so that you can use all of the eggs.

To scale a recipe to have a specific amount of an ingredient, you need to multiply each ingredient by the desired amount of the specific ingredient divided by its original amount.

If we want to adjust a specific ingredient so that the recipe has exactly 300g and the recipe originally called for 120g, then you will need to calculate a multiplier by dividing 300 by 120 which is 2.5. Then you can multiply each ingredient by 2.5

Formula

For each ingredient: 

original ingredient amount × desired amount of specific ingredient ÷ original amount of specific ingredient

Example

Cedric wants to make choux and has a recipe that requires 4 eggs. He has 5 eggs left and wants to use all of it.

Choux Recipe with 4 Eggs 

• 125g milk
• 125g water
• 5g salt
• 100g unsalted butter
• 150g all-purpose flour
• 4 large eggs

Cedric multiplies each ingredient by 5 and then divides by 4 to get the desired recipe.

Choux Recipe with 5 Eggs 

• 156g milk (125 × 5 ÷ 4)
• 156g water (125 × 5 ÷ 4)
• 6g salt (5 × 5 ÷ 4)
• 125g unsalted butter (100 × 5 ÷ 4)
• 188g all-purpose flour (150 × 5 ÷ 4)
• 5 large eggs (4 × 5 ÷ 4)

Specific Ingredient Amount Recipe Calculator

We made this calculator to help you scale a recipe to a specific ingredient, so that you can save time and spend more time cooking instead of fiddling with these complex formulas.

How to Scale a Recipe to Have a Specific Total Amount

To scale a recipe to have a specific total amount you need to multiply each ingredient by a multiplier calculated by dividing the desired total amount by the original total amount.

Formula

To calculate the amount for each ingredient:

original ingredient amount × desired total amount ÷ original total amount

Example

Roger has a white chocolate gianduja recipe that totals 160g. He recently bought a new silicone mould that has 20 cavities that fit 10g of gianduja per cavity. He needs exactly 200g of gianduja to fill the mould. He decides to make 220g of gianduja to make a little extra.

White Chocolate Gianduja Recipe - 160g Total

• 110g white chocolate
• 50g hazelnut paste

Roger divides 220 by 160 (dividing the desired total amount by the original total amount)

White Chocolate Gianduja Recipe - 220g Total

• 137.5g white chocolate (100 × 220 ÷ 160)
• 68.75g hazelnut paste (50 × 220 ÷ 160)

Specific Total Amount Recipe Calculator

This calculator helps you scale a recipe to a specific total amount.

How to Scale a Recipe by Size and Shape (Volume)

To scale a recipe to have a different size or shape you will need to calculate the volume of the original shape and the desired volume. Then you can calculate a multiplier by dividing the desired volume by the original shape. Note: recipes often don’t scale linearly when dealing with volumes. I.e., a cake recipe for a 20-inch tin is not the same as multiplying a 10-inch tin recipe by 2.

Formula

To calculate the amount for each ingredient:

original ingredient amount × desired volume ÷ original volume

Example

Nadine wants to make a Torte cake and has a 10-inch cylinder tin but the recipe is for a 8-inch cylinder tin.

Torte Recipe for 8-inch Cylinder Tin

• 250g hazelnut meal
• 250g dark chocolate
• 225g butter
• 200g caster sugar
• 6 eggs

She calculates the volume for the 8-inch cylinder tin, assuming a height of 2 inches: 

π × 42 × 2 = 100in3

She then calculates the volume for the 10-inch cylinder tin, assuming the same height of 2 inches: 

π × 52 × 2 = 157in3

Torte Recipe for 10-inch Cylinder Tin

• 392g hazelnut meal (250 × 157 ÷ 100)
• 392g dark chocolate (250 × 157 ÷ 100)
• 353g butter (225 × 157 ÷ 100)
• 314g caster sugar (200 × 157 ÷ 100)
• 9 eggs (6 × 157 ÷ 100)

Recipe Resizer Mobile App - The Recipe Scaling Calculator

Scaling recipes can be tedious and error prone, so we made an app to take care of all of the complex math so that you can scale recipes instantly. Recipe Resizer helps you save time and avoid fumbling over formulas with a simple interface to resize a recipe and scale the ingredients up or down to suit your needs. Recipe Resizer helps you to be precise, avoid mistakes and save time so that you can spend less time doing maths and more time cooking, baking and creating.

Catering for a larger number of people? This Recipe Resizer app resizes recipes instantly to have the amount of servings you need.

Ever had a leftover ingredient and wanted to scale your recipe to use up all of that ingredient? Recipe Resizer allows you to specify exactly how much you want of an ingredient, and it will automatically scale the other ingredients to keep the same ratio.

Ever wanted to make a specific amount of a recipe? Recipe Resizer allows you to specify the desired total weight of the recipe, and it will resize all the ingredients so that they add up to exactly what you need!

Recipe Resizer is a recipe scaling calculator where all you need to do is provide the inputs and it will tell you the answer. It is suitable for all your recipe scaling needs, so whether you're scaling up a cake recipe or require that precision for scaling baking recipes, Recipe Resizer is the tool you need.

We designed this tool because we wanted to avoid the complex and time-consuming math involved with scaling recipes. It has honestly been really useful and we now use it all the time! We want to bring a user-centric approach to the app and are interested in your feedback so we can add what you need. Let us know if there is something Recipe Resizer could do to make your life in the kitchen easier.