Recipe Scaler (Adjust Servings)
Scale any recipe up or down by changing the serving count. Multiplies every ingredient quantity proportionally.
What this calculates
Recipes are written for a specific serving count, but real cooking rarely matches. Doubling for a dinner party or halving for one person requires multiplying every quantity by the same ratio. This calculator does it for any number of ingredients at once, in cups, grams, ounces, teaspoons — whatever your recipe uses.
Formula & how it works
Scale factor = target_servings ÷ original_servings. New quantity = original quantity × scale factor. Works identically for any unit because the unit doesn't change — only the number does.
Worked example
A 4-serving cookie recipe with 2 cups flour, 1 cup sugar, 2 eggs, 1 tsp vanilla. Scale to 6 servings → factor = 6 ÷ 4 = 1.5. New quantities: 3 cups flour, 1.5 cups sugar, 3 eggs, 1.5 tsp vanilla. Round eggs up (you can't add half an egg easily — most bakers either use the smaller egg count or beat 1.5 eggs by weight).
Frequently asked questions
Does scaling work for any recipe?
Most yes. Bread, cookies, soups, sauces — all scale linearly. Baking with chemical leaveners (cake, muffins) can misbehave at extreme scales because pan geometry and oven heat don't scale. Roughly 0.5–3× is safe; beyond that, rebake-test.
What about cooking time?
Cooking time scales with thickness, not volume. A doubled pot of soup takes only slightly longer to come to a boil. A doubled cake batter in a bigger pan takes ~50 % more time. A doubled roast takes only ~20 % more.
Should I round to nice numbers?
For everyday cooking, yes — your taste won't notice the difference between 0.83 cups and 1 cup. For baking, the original ratio matters more, so prefer awkward fractions over rounding.
How do I scale fractions?
Convert to decimal first (1/2 = 0.5), multiply, then convert back if you want. 3/4 cup × 1.5 = 1.125 cups = 1 cup + 2 tablespoons. The decimal route is less error-prone.