Recipe Scaler

How to use this calculator

Paste or type the ingredients, one per line, as they appear in the recipe: “1 1/2 cups milk”, “½ tsp salt”, “200 g butter” and “3 eggs” are all understood, as are ranges such as “2–3 cloves garlic”. Lines without a number (“salt to taste”) are kept as they are. Enter the servings the recipe makes and the servings you want, or type a scale factor directly — halving is 0.5, doubling is 2.

To work backwards from your pantry, choose an ingredient under “Limit by an ingredient you have” and enter how much of it you have, in the same unit the recipe uses. The factor and number of servings are recalculated so that ingredient is used up exactly, and everything else is scaled to match.

The formula

k = servings_new / servings_original

q′ = k × q

k = q_have / q (when limited by one ingredient)

k: scale factor = new servings ÷ original servings
q: quantity of an ingredient in the original recipe
q′: scaled quantity

Worked example

A pancake recipe serves 4 and calls for 2 cups flour, 1½ tsp baking powder, 3 tbsp sugar and 1¼ cups milk. You are cooking for 6.

Scale factor k = 6 ÷ 4 = 1.5.
Flour 2 × 1.5 = 3 cups; baking powder 1½ × 1.5 = 2¼ tsp; milk 1¼ × 1.5 = 1⅞ cups.
Sugar 3 tbsp × 1.5 = 4½ tbsp. Amounts that land between spoon sizes are written as, say, “1 tbsp + 1 tsp”, and 4 tbsp or more becomes cups when that is simpler.

Every ingredient is multiplied by the same factor; only the presentation changes so the amounts match your measuring set.

US kitchen measures

Measure	Equals
1 tablespoon	3 teaspoons (14.8 mL)
¼ cup	4 tablespoons
⅓ cup	5 tablespoons + 1 teaspoon
1 cup	16 tablespoons = 8 US fl oz (236.6 mL)
1 pound	16 ounces (453.6 g)

Measures follow NIST Handbook 44 definitions of the US customary units.

Assumptions and limits

Ingredients scale linearly. Leavening, salt and spices sometimes need less than a straight multiple in very large batches; taste and adjust.
Baking time and pan size do not scale with the recipe — use the baking pan converter to pick a pan, and check doneness early.
Eggs are shown as fractions when needed; beat the egg and measure about 50 g (3¼ tbsp) per large egg.

Frequently asked questions

How do I halve a recipe with 3 eggs?

Use 1½ eggs: beat two eggs together and use three-quarters of the mixture, or one whole egg plus about 25 g of beaten egg.

Should I convert cups to grams before scaling?

Weighing is more accurate, especially for flour. Use the cups to grams calculator to convert, then scale the weights.

Does cooking time change when I double a recipe?

Not proportionally. A deeper pan takes longer to cook through; two pans of the original size usually bake in the original time.