Recipe Scaler
A recipe for 4 when you're feeding 6 — or 12. Enter the ingredients once and get every amount rescaled in kitchen fractions, not awkward decimals.
scale factor: 1 1/2×
Accepts fractions (3/4), mixed numbers (1 1/2), and decimals; results round to the nearest kitchen fraction. Scaling caveats: seasonings and leavening don't scale perfectly linearly (taste as you go, and slightly under-scale spices when doubling), and baking times change with pan size — not with the recipe multiple.
Scaling a Recipe Without Ruining It
The arithmetic is a single ratio — new servings divided by original — applied to every ingredient. The craft is in the exceptions: salt, spices, and chili scale to taste rather than to math (start at about 75% of the scaled amount when doubling), leavening like baking powder slightly under-scales in big batches, and cooking time follows the vessel, not the volume. A doubled casserole in a deeper dish bakes longer at the same temperature; doubled cookies on two trays bake the same time per tray.
Handy kitchen fractions
Scale factor = servings you need ÷ recipe servings 3/4 cup × 1.5 = 1 1/8 cups 1 1/2 tsp × 2/3 = 1 tsp 1 cup = 16 tbsp = 48 tsp (useful when thirds get ugly: 1/3 cup × 1.5 = 1/2 cup, but 1/4 cup × 1/3 = 4 tsp)
Frequently Asked Questions
Can I just double everything in a recipe?
For most savory cooking, yes. The exceptions: salt, chili, and strong spices (start at ~75% of the doubled amount and adjust to taste), leavening in baked goods (slightly under-scale in large batches), and cooking time — which follows pan size and depth, not the recipe multiple.
How do I scale half an egg?
Whisk a whole egg until uniform, then measure half — about 2 tablespoons (a large egg is roughly 50 g out of the shell, so 25 g by weight). For amounts smaller than that, many bakers just round the recipe to the nearest whole egg and accept slightly richer results.
Why do baking recipes scale worse than cooking recipes?
Baking is chemistry with ratios — flour to liquid to fat to leavening — and pan geometry changes how heat reaches the center. A doubled cake in the same pan won't bake through before the edges dry out. Scale baking by weight, keep pan depth similar, and expect to adjust time, not temperature.
Is it better to scale recipes by weight than by cups?
Much better, when you have gram amounts: 347 g × 1.5 is exact, while 1½ cups × 1.5 forces awkward fraction rounding, and cup measurements of flour already vary ±20% by how you scoop. This is the main reason serious baking recipes are written in grams.