Recipe Scaler
A recipe for 4 that uses "1 1/2 cups flour" needs "2 ¼ cups flour" for 6 servings, because the scale factor is 6 / 4 = 1.5.
How to use
- Paste the ingredients, one per line, with the quantity at the start of each line.
- Enter the servings the recipe makes and the servings you want.
- Pick fractions or decimals for the result, then copy the scaled list.
How it works
The scale factor is the wanted servings divided by the original servings. Every quantity at the start of a line is multiplied by it. Cooking for 6 from a recipe for 4 gives a factor of 1.5.
The tool reads whole numbers, decimals (1.5), fractions (1/2), mixed numbers (1 1/2 or 1-1/2), fraction characters (½ ⅓ ⅔ ¼ ¾ ⅛ and others), joined mixed numbers (1½) and ranges (2-3 or 2 to 3). Both ends of a range are scaled.
In fraction mode, amounts under 10 are rounded to the nearest of 1/8, 1/4, 3/8, 1/2, 5/8, 3/4, 7/8, 1/3 and 2/3. When two fractions are equally close, the smaller one is used. Amounts of 10 and over are shown as decimals, rounded to one decimal place, or to a whole number from 100.
In decimal mode, amounts under 10 are rounded to two decimal places and amounts from 10 to 99 to one decimal place.
Lines without a quantity at the start, such as "salt to taste", are left as they are. Text after the quantity, including units and notes in brackets, is not changed.
FAQ
Why was a number in the middle of a line not scaled?
Only the quantity at the very start of a line is changed. A line such as "Juice of 1 lemon" or "1 cup flour plus 2 tbsp for dusting" keeps its inner numbers, so check those by hand.
Do unit sizes in brackets change?
No. In "2 (14 oz) cans tomatoes" only the 2 is scaled. The 14 oz is the size of each can, so it stays.
Can I scale a recipe by a factor instead of servings?
Yes. Enter 1 as the original servings and the factor as the wanted servings. For example 1 and 2 doubles every quantity.
Does scaling work for baking times, pan sizes and spices?
No. The tool only scales the quantities you paste. Cooking time, pan size and strong flavours such as chilli or salt often do not scale in a straight line, so taste and adjust.
Why does 1,5 kg not scale?
A comma between digits can mean a thousands separator or a decimal comma, so the tool leaves the line unchanged rather than guess. Write 1.5 kg instead.