Recipe Scaling Calculator
Scale any recipe up or down by entering the original servings and your desired number. Enter one ingredient or paste a short ingredient list to see scaled quantities with fraction-friendly kitchen rounding.
Formulas, assumptions, and rounding are documented in our calculator methodology.
Scale an Ingredient
Scale Factor
x2
4 servings to 8 servings
Scaled Ingredient
- Original (4 servings)
- 2 cups
- Scaled (8 servings)
- 4 cups
Start each line with a number, decimal, or fraction. Examples: 2 cups flour, 1/2 tsp salt, 3 eggs.
| Original | Scaled |
|---|---|
| 2 cups flour | 4 cups flour |
| 1 1/2 tsp salt | 3 tsp salt |
| 3 eggs | 6 eggs |
Recipe Scaling Formula
Scale factor = desired servings divided by original servings. New ingredient quantity = original quantity times scale factor. Example: a recipe serves 4 and you need 10 servings. Scale factor = 10 divided by 4 = 2.5. Every ingredient is multiplied by 2.5: 1 cup flour becomes 2.5 cups, 2 teaspoons salt becomes 5 teaspoons, and 3 eggs becomes 7.5 eggs.
Fraction Handling and Smart Rounding
The calculator accepts decimals, simple fractions, and mixed numbers such as 0.5, 1/2, and 1 1/2. Scaled results are rounded toward common kitchen fractions when they are close to an eighth, quarter, third, half, two-thirds, or three-quarters. For small amounts such as salt, vanilla, baking powder, and yeast, use the rounded result as a starting point and adjust carefully.
Examples: Doubling, Halving, and Odd Serving Counts
To double a recipe, multiply by 2: 1 1/2 cups milk becomes 3 cups. To halve a recipe, multiply by 0.5: 3/4 cup sugar becomes 3/8 cup, which is 6 tablespoons. To scale 4 servings to 7 servings, multiply by 1.75: 2 tablespoons oil becomes 3 1/2 tablespoons. Unusual serving counts often create awkward amounts, so round seasonings conservatively and taste near the end.
Leavening Agents: The Exception to Linear Scaling
Baking powder, baking soda, and yeast do not always scale proportionally. For batches scaled up more than 2×, reduce the calculated leavening by about 25% and test a small batch first. Too much baking powder can make baked goods taste bitter and collapse. Salt also follows a linear scale but should be verified to taste, as its perception can intensify in very large batches.
Whole Items: Eggs, Cans, Packets, and Produce
Ingredients sold or used as whole items rarely scale perfectly. For half an egg, beat it and measure about 2 tablespoons, or round to a whole egg in pancakes, muffins, meatballs, and other forgiving recipes. For canned tomatoes, broth cartons, seasoning packets, lemons, onions, and garlic cloves, round to the nearest practical amount and then balance thickness, liquid, salt, acid, and seasoning.
Pan Size and Baking Time Adjustments
Scaling a recipe often means using a different pan size, which affects baking time and texture. Keep the food depth close to the original whenever possible. A doubled batter split between two pans usually behaves more predictably than one very deep pan. A shallower pan cooks faster and browns more quickly; a deeper pan often needs more time. Start checking 10 to 15 minutes early and use doneness cues instead of scaling the timer directly.
Frequently Asked Questions
- Most ingredients scale linearly and work well with a simple multiplier. However, leavening agents (baking powder, baking soda, yeast) do not always scale proportionally for large batches — use only 75% of the calculated amount for baking powder and soda when scaling up more than 2×. Spices should be scaled and then adjusted to taste.
- Scale factor = desired servings divided by original servings = 6 divided by 4 = 1.5. Multiply every ingredient by 1.5. Example: 2 cups flour becomes 3 cups flour. 1 teaspoon salt becomes 1 1/2 teaspoons salt. 3/4 cup sugar becomes 1 1/8 cups sugar.
- For halving, divide each ingredient by 2. Common fractions: half of 3/4 cup is 6 tablespoons, or 1/4 cup plus 2 tablespoons. Half of 1/3 cup is 2 tablespoons plus 2 teaspoons. Half of 1 egg can be handled by beating the egg and using about 2 tablespoons. Half of 1/2 teaspoon is 1/4 teaspoon.
- No — cooking times do not scale linearly with recipe size. When doubling a stovetop recipe, the cooking time may increase slightly. For baked goods, a doubled batch in a larger pan usually takes 1.2–1.5× longer, not 2×. When in doubt, start checking for doneness 10–15 minutes before the expected finish time.
- Whole items need judgment. For eggs, beat the egg and measure a partial amount when precision matters, or round to the nearest whole egg for forgiving recipes. For cans, packets, lemons, onions, and similar ingredients, round to a practical amount and adjust liquid, seasoning, or texture as needed.
- You can paste simple ingredient lines that begin with a number or fraction, such as 2 cups flour, 1 1/2 tsp salt, or 3 eggs. The parser is meant for common quantity-unit-ingredient lines, not full recipe directions, temperature notes, or complex parenthetical package sizes.
- Try to keep the batter or food depth close to the original recipe. Doubling a 9-by-13-inch pan recipe often works better as two pans than one much deeper pan. If the depth changes, start checking early and rely on doneness cues such as internal temperature, set edges, or a clean tester.