Enrichment · Arts and Creativity · Kitchen

Half again as much,
measured with the
spoons you own.

Type how many the recipe serves, how many you need and each ingredient. Every amount is multiplied by the same factor and written as cups, tablespoons and teaspoons you can measure, not as 2.625 cups.

Scale a recipeWhat you get

The recipe scaler

The worked example is a made-up banana bread for 8, scaled to 12. Nothing you type leaves this browser.

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What you get

Enrichment · Arts & CreativityFree

What you finish with
The whole recipe at the new size, each ingredient as a decimal and as a measure you can scoop, with notes on pans, time and leavening. It prints as a recipe card and downloads as a spreadsheet.
Who it is for
Students learning to cook, families feeding more or fewer people, and culinary or family and consumer sciences classes practising proportion.
Format
Browser calculator for a phone, tablet or computer, by touch or keyboard. Up to 40 ingredients. Prints the scaled recipe; downloads a spreadsheet (.csv); export and import a file.
Access
Free. No account, no sign-in and nothing to install. Everything you type stays in this browser; nothing is sent to Caveat.
Where it lives
The Arts & Creativity space in Caveat Enrichment.
Support
Questions, a correction or a request: team@caveatacademic.com.

How to use it

  1. Type the recipe name, how many it serves and how many you want.
  2. Add each ingredient with its amount and unit as the recipe gives it.
  3. Read the scale factor and the new measure for each ingredient.
  4. Read the notes on pans, time and leavening before you bake.
  5. Print the scaled recipe for the kitchen.

Scale a recipe

How the amounts are scaled

One factor for every ingredient, then back into spoons and cups.

The worked example: the flourFactor×1.512 servings ÷ 8Flour, 1 3/4 cups84 tsp1.75 × 48 tspScaled126 tsp84 × 1.5Measure2 1/2 cups + 2 tbsp120 tsp + 6 tspThe worked example: the flourFactor×1.512 servings ÷ 8Flour, 1 3/4 cups84 tsp1.75 × 48 tspScaled126 tsp84 × 1.5Measure2 1/2 cups + 2 tbsp120 tsp + 6 tsp
Volume measures are turned into teaspoons, multiplied, and written back in the largest spoons and cups that fit, so 2.625 cups reads as 2 1/2 cups and 2 tablespoons.

The arithmetic

The factor is the servings you want divided by the servings the recipe makes. Each amount is multiplied by it. Cups and spoons are converted to teaspoons first (1 cup is 48 teaspoons, 1 tablespoon is 3), rounded to the nearest eighth of a teaspoon, then written as quarter cups, whole tablespoons and the teaspoons left over. Grams, ounces, pounds and millilitres stay as numbers, which is why weighing is the most accurate way to scale.

What does not scale in a straight line

Ingredients scale; physics does not. A bigger loaf in the same pan is deeper and needs longer at the same temperature, or a second pan. Salt, spices, baking soda and baking powder taste strong first when a recipe is doubled or more, so add them at the scaled amount and taste. Eggs come in wholes: beat one and use about 2 tablespoons for half.

Sources

  1. U.S. Department of Agriculture, Food and Nutrition Service. Food Buying Guide for Child Nutrition Programs: measures and equivalents (fns.usda.gov).
  2. National Institute of Standards and Technology. Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices, Handbook 44, appendix C: US customary units of volume (nist.gov).
  3. National Institute of Standards and Technology. NIST Special Publication 1038, The International System of Units: Interpretation and Use in the United States, conversion factors for the US cup and tablespoon.
  4. Cooperative Extension (land-grant universities). Guidance on adjusting recipe yields and household measures, as published by state extension services.

The worked example is made up. Scaled amounts are rounded to measures you can use; for baking, weighing the ingredients is more accurate. Your recipe stays in this browser. Support: team@caveatacademic.com.