Recipe Scaling
This free recipe scaling calculator adjusts every ingredient's quantity for a new number of servings, so doubling a recipe or cutting it in half takes one calculation instead of doing the math for each ingredient by hand. Nothing you enter is sent anywhere or stored.
How to Use It
- Enter the recipe's original number of servings and the new number of servings you want.
- Add each ingredient with its quantity and unit.
- Every scaled quantity updates instantly as you type, no submit button.
How It Works
This calculator divides the new number of servings by the original number of servings to find a single scale factor, then multiplies every ingredient's quantity by that same factor. A recipe scaled from 4 servings to 6 uses a 1.5× scale factor; scaled down to 2 servings, it uses a 0.5× scale factor instead.
Formula
scale factor = new servings ÷ original servings
scaled quantity = original quantity × scale factor
A worked example: a recipe serving 4 that calls for 2 cups flour, 1 cup sugar, and 0.5 cup butter, scaled up to serve 6 (a 1.5× scale factor), needs 3 cups flour, 1.5 cups sugar, and 0.75 cup butter. Scaled down to serve 2 instead (a 0.5× scale factor), the same recipe needs 1 cup flour, 0.5 cup sugar, and 0.25 cup butter.
Everything runs client-side in your browser. Nothing you enter is sent anywhere or stored.
Frequently Asked Questions
How is this different from the Cooking Measurement Converter?
The Cooking Measurement Converter changes a quantity from one unit to another, cups to milliliters, for example, without changing the recipe itself. This calculator keeps every ingredient in its original unit and instead scales every quantity for a different number of servings, so doubling a recipe or cutting it in half takes one calculation instead of doing the math for each ingredient by hand.
How do I enter a fraction like 1/2 cup?
Enter it as a decimal: 1/4 is 0.25, 1/3 is about 0.33, 1/2 is 0.5, and 3/4 is 0.75. A mixed amount like "1 1/2 cups" is entered as 1.5. This matches how the existing Cooking Measurement Converter also expects quantities.
Is doubling a recipe always as simple as multiplying every ingredient by 2?
Usually, but not always. Salt, spices, and leavening agents like baking soda, baking powder, or yeast often need proportionally less than a straight multiplication once a recipe is scaled up significantly, since their effect doesn't always increase linearly with quantity. This calculator handles the arithmetic; a large scale-up on a baked recipe in particular is worth double-checking against a similar recipe at that size.
What about pan size when I scale up a baked recipe?
Pan size and baking time don't scale the same way ingredient quantities do. Doubling a cake recipe usually needs a larger pan or two pans of the original size, not the same pan filled twice as high, and the baking time typically needs adjusting too. This calculator only handles ingredient quantities, pan size and timing still need a judgment call based on the specific recipe.
Can you give a real-world example?
A recipe serving 4 that calls for 2 cups flour, 1 cup sugar, and 0.5 cup butter, scaled up to serve 6, needs 3 cups flour, 1.5 cups sugar, and 0.75 cup butter (each multiplied by the 1.5× scale factor). Scaled down to serve 2 instead, the same recipe needs 1 cup flour, 0.5 cup sugar, and 0.25 cup butter (each multiplied by a 0.5× scale factor).