Пересчёт рецепта

Scale a recipe to any number of servings: each ingredient is multiplied by new ÷ original servings, with cups and spoons shown as kitchen fractions.

Обновлено 28 сентября 2026 г.Проверенные примеры: 5

Scale factor

Максимум знаков после запятой: 4; До ближайшего, при равенстве — от нуля

Scaled recipe: 3 cups flour; 2 1/4 tsp salt; 1 1/8 cup sugar; 3 eggs; 1/2 cup milk; 375 g butter
Lines scaled: 6
Lines kept as written: 0

Every amount is multiplied by 1.5 to go from 4 to 6 servings; 6 of 6 lines had an amount to scale.

Servings

Scaled ingredients Строк: 6

Ingredient	Original	Scaled	Точно
cups flour	2	3	3
tsp salt	1 1/2	2 1/4	2.25
cup sugar	3/4	1 1/8	1.125
eggs	2	3	3
cup milk	1/3	1/2	0.5
g butter	250	375	375

Как выполняется расчёт S

Scale factor
$\frac{6}{4} = 1.5$
Scale each amount (first line: cups flour)
$\text{2} \times 1.5 = 3$
Shown as 3.
How amounts are shown
Cups, spoons and counts are rounded to the nearest kitchen fraction (eighths, quarters, thirds, halves); ≈ marks a rounded value. Grams, kilograms, millilitres and litres are shown as decimals to 2 places.

О калькуляторе: Пересчёт рецепта

Every amount is multiplied by the scale factor: the servings you need divided by the servings the recipe makes. Cup, spoon and count amounts are rounded to the nearest measure a kitchen set holds (eighths, quarters, thirds and halves) and marked ≈ when rounded. Grams, kilograms, millilitres and litres stay as decimals.

The default recipe goes from 4 to 6 servings, a factor of 1.5, so 3/4 cup of sugar becomes 1 1/8 cups and 250 g of butter becomes 375 g. The Institute of Child Nutrition teaches the same two steps for school kitchens: 35 servings from a 25-serving recipe is a factor of 1.4, which turns 3 cups of tomatoes into 4.2 cups, rounded to 4 1/4.

Lines without a number, such as "salt to taste", are kept as written. Baking time, pan size and seasoning do not scale in proportion, so check them separately.

Примеры с решением

Default recipe from 4 to 6 servings

Ingredients, one per line: 2 cups flour 1 1/2 tsp salt 3/4 cup sugar 2 eggs 1/3 cup milk 250 g butter
Recipe makes (servings): 4
Servings you need: 6

Scale factor: 1.5
Scaled recipe: 3 cups flour; 2 1/4 tsp salt; 1 1/8 cup sugar; 3 eggs; 1/2 cup milk; 375 g butter

Источник проверки: Python fractions: 2×3/2 = 3, 3/2×3/2 = 9/4, 3/4×3/2 = 9/8, 1/3×3/2 = 1/2, 250×3/2 = 375

Halving

Ingredients, one per line: 1 cup sugar 2 tbsp butter 1 egg
Recipe makes (servings): 4
Servings you need: 2

Scale factor: 0.5
Scaled recipe: 1/2 cup sugar; 1 tbsp butter; 1/2 egg

Источник проверки: Python fractions: each amount × 1/2

Unscaled line, unicode fraction, range and an approximate fraction

Ingredients, one per line: Salt to taste 1½ cups oats 2-3 cloves garlic 1 cup milk
Recipe makes (servings): 6
Servings you need: 5

Scaled recipe: Salt to taste; 1 1/4 cups oats; 1 2/3–2 1/2 cloves garlic; ≈ 7/8 cup milk
Lines kept as written: 1
Lines scaled: 3

Источник проверки: Python fractions: 3/2×5/6 = 5/4; 2×5/6 = 5/3, 3×5/6 = 5/2; 5/6 = 0.833 is nearest 7/8 among eighths and thirds

25 to 35 servings (ICN worked example)

Ingredients, one per line: 3 cups tomatoes
Recipe makes (servings): 25
Servings you need: 35

Scale factor: 1.4
Scaled recipe: ≈ 4 1/4 cups tomatoes

Источник проверки: Institute of Child Nutrition, Adjusting Standardized Recipes: 35 ÷ 25 = 1.4; 3 cups × 1.4 = 4.2 cups, rounded to 4 ¼ cups

Вопросы

How do you scale a recipe up or down?

Divide the servings you need by the servings the recipe makes, then multiply every ingredient by that factor. Going from 4 to 6 servings is a factor of 1.5, so 2 cups of flour becomes 3 cups; going from 4 to 2 is 0.5. The Institute of Child Nutrition advises converting mixed amounts such as 1 lb 8 oz to one unit (1.5 lb) before multiplying.

What is half of 1/3 cup or 3/4 cup?

Half of 1/3 cup is 1/6 cup: 2 tablespoons plus 2 teaspoons, because a US cup holds 16 tablespoons and a tablespoon holds 3 teaspoons. Half of 3/4 cup is 3/8 cup, or 6 tablespoons. When no standard measure matches, the calculator shows the nearest eighth or third with ≈ and gives the exact decimal in the table.

Does baking time change when you double a recipe?

Often, because baking time depends on the depth of the batter more than on its amount. Doubled batter in the same pan is twice as deep and needs longer; spread over a pan with twice the area, it keeps its depth and bakes in close to the original time. Keep the oven temperature the same and test for doneness early.

Is a cup the same size in every country?

No. A US customary cup is 8 US fluid ounces, 236.6 mL, while the metric cup used in Australia and New Zealand is 250 mL, about 6% larger. Scaling works the same in both systems because every amount is multiplied by the same factor. NIST advises weighing ingredients on a kitchen scale for accuracy rather than measuring by volume.

Насколько точен «Пересчёт рецепта»?

Точность зависит от введённых данных и допущений метода. Десятичная арифметика использует 50 значащих цифр, но оценки, численные методы и исходные данные могут быть менее точными; округление на экране не устраняет эти ограничения. Решённые примеры, проверенные по независимым источникам: 5. Например, «Default recipe from 4 to 6 servings» проверяется по источнику Python fractions: 2×3/2 = 3, 3/2×3/2 = 9/4, 3/4×3/2 = 9/8, 1/3×3/2 = 1/2, 250×3/2 = 375.

Откуда взята методика?

Institute of Child Nutrition — Adjusting standardized recipes (factor = new yield ÷ old yield); NIST Metric Kitchen — Culinary measurement tips.

Об этом калькуляторе

\text{new} = \text{old} \times \frac{\text{servings needed}}{\text{servings made}}

Источники

Проверено по источникам

В калькулятор включены решённые примеры с ответами из независимых источников. Их количество: 5. Они входят в набор тестов, и вы также можете запустить их здесь.