How to scale a recipe by servings

The serving ratio

To go from 4 servings to 6, multiply every ingredient by 6 ÷ 4 = 1.5. Two cups of broth become three cups. The Recipe Scaling Calculator applies that ratio to a single amount at a time so you can move down a recipe card without redoing the division by hand.

Weight beats volume when you can

Grams scale more cleanly than packed cups of flour. If your recipe lists weights, scale the weights. If it lists cups, the Cooking Measurement Converter helps when you need millilitres or tablespoons, with the usual caveat that a US cup is not a 250 ml metric cup.

Spices, salt, and yeast

Salt, hot spices, and yeast do not always taste right when scaled linearly over a large jump. When you double a soup, start a little under on chilli and salt, then adjust. For bread, baker’s percentages keep hydration and salt in proportion; see the Baker’s Percentage Calculator.

Pan size and bake time

Tripling a cake batter may need a larger pan or multiple pans. Depth changes bake time more than the serving math does. Check early with a skewer rather than multiplying time by the same ratio.

Worked example

A sauce that uses 2 cups of tomatoes for 4 servings becomes 3 cups for 6 servings. A spice at 1 teaspoon becomes 1.5 teaspoons. If you only have a 1 teaspoon measure, use one full teaspoon plus a half teaspoon.

Oven temperatures

Scaling servings does not change oven temperature. When a recipe lists gas mark or only Celsius, use the Oven Temperature Converter. Fan settings are a separate instruction from the recipe author; do not convert twice.

Checklist before you buy or rely on the number

Write down the raw inputs you used, including units. Re-run the calculator once with those exact figures. If a store pack size or a syllabus rule forces a round-up, round up rather than chasing a perfect match. Keep a note of the date you calculated so you can compare later when prices, labels, or grades change.

A note on units

Keep units consistent inside one calculation. Mixing feet with metres, or cups with grams without a density, is the usual source of bad results. When a label uses a different unit, convert once with the Unit Converter and then return to the specialty calculator.

Limits

These figures are planning aids. Confirm product labels, syllabus rules, employer policy, or veterinary advice when a decision depends on the number.