KitchenScale

Recipe Scaler Calculator

Turn a recipe for 4 into a recipe for 6 (or 2) — every ingredient scales by the same ratio.

Original ingredient amount

Original servings

New servings

Scaled amount

Works for any ingredient unit (cups, grams, tablespoons) — the ratio is what matters.

What you entered

Original ingredient amount: 2Original servings: 4New servings: 6

1
Scale factor
6 ÷ 4= 1.5×
2
Scaled ingredient amount
2 × 1.5= 3

Result

Scaled amount: 3

Scaling from 4 to 6 servings turns 2 into 3 of this ingredient.

Scaling a recipe ingredient up or down

The scale factor is the new serving count divided by the original. Every ingredient is multiplied by it.

Original amount	Original servings	New servings	Scale factor	Scaled amount
300	8	3	0.3750	112.5000
500	4	2	0.5000	250.0000
1.5	6	4	0.6667	1.0000
250	4	6	1.5000	375.0000
2	4	10	2.5000	5.0000

Straight multiplication works for the bulk ingredients - flour, liquid, sugar, protein - but not for everything. Baking times do not scale linearly, since a larger volume takes disproportionately longer to heat through, and pan size matters more than the recipe suggests: doubling a cake batter needs a bigger tin, not a deeper one. Raising agents, salt and strong spices often need slightly less than the factor implies when scaling up, and alcohol and gelatine behave differently again. Scale the ingredients here, then adjust seasoning by taste.

Not everything scales linearly in real cooking

The math is a straight ratio, but seasonings, leavening agents (like baking soda), and cooking times don't always scale perfectly linearly in practice — taste and adjust seasoning, and watch bake times when doubling or tripling a recipe.

Works for any unit

Whether the original amount is in cups, grams, tablespoons, or a whole number of eggs, the same scale factor applies — just apply the result thoughtfully when it produces an awkward fraction (like 1.33 eggs).

Frequently asked questions

A cookie recipe makes 24 cookies and I need 36 — how do I scale the ingredients?

The scale factor is 36 ÷ 24 = 1.5. Multiply every ingredient by 1.5: if the recipe calls for 2 cups flour, use 3 cups; 1 tsp vanilla becomes 1.5 tsp; 2 eggs becomes 3 eggs.

Can I just double the baking soda when I double a recipe?

Technically the math says yes, but in practice leavening agents (baking soda, baking powder, yeast) don't always scale linearly — doubling can over-leaven, giving a metallic taste or collapsed texture. Start with 1.5× and adjust by taste.

What do I do when scaling gives me an awkward number like 1.33 eggs?

Beat a whole egg, measure its volume (~3 tablespoons for a large egg), then use 1/3 of that for the fractional portion. For ingredients like butter or flour, just round to the nearest practical measurement — ±5% won't ruin most recipes.

Does cooking time change when I scale a recipe up?

Cooking time doesn't scale linearly with ingredient volume. Doubling a cake recipe doesn't mean doubling the bake time — it might add 25–50%. Use a thermometer or visual cues rather than relying on the clock. Soups and stews are more forgiving.