Serving Size Calculator - Scale Any Recipe Up or Down

Double it, halve it, scale it to 17 - the math stays clean

A recipe serves 4 but dinner is for 7. Or you found a cake recipe for 12 and need exactly 3 portions for the week. Enter up to 10 ingredients with their original amounts, set the target serving count, and the calculator multiplies every line by the same ratio. No rounding guesswork, no mental arithmetic with fractions of a teaspoon.

How to scale a recipe - step by step

Recipe serves - enter how many servings the original recipe makes. Most recipes state this at the top ("serves 4", "makes 12 cookies").
I need servings - enter your target number. Doubling? Enter 8 for a recipe that serves 4. Halving? Enter 2.
How many ingredients? - select 1 to 10. Only the fields you need will appear.
Fill in each ingredient - name, amount and unit from the original recipe. The unit carries over unchanged (grams stay grams, cups stay cups).
Read the results - a side-by-side table shows original vs scaled amounts, plus the multiplication factor.

Common scaling ratios

Quick reference for the most frequent recipe adjustments.

Scenario	Original	Target	Factor
Double the recipe	4	8	2.0x
Halve the recipe	6	3	0.5x
Dinner party (4 to 10)	4	10	2.5x
Cooking for one (4 to 1)	4	1	0.25x
Triple batch of cookies	24	72	3.0x
Odd number (4 to 7)	4	7	1.75x

Worked example - pasta for 7 instead of 4

Original recipe (4 servings): Pasta 400 g, olive oil 3 tbsp, garlic 4 pcs, parmesan 80 g, salt 1 tsp
Factor: 7 / 4 = 1.75x
Scaled (7 servings): Pasta 700 g, olive oil 5.25 tbsp, garlic 7 pcs, parmesan 140 g, salt 1.75 tsp

Halving a cake (12 to 6): Flour 300 g becomes 150 g, eggs 4 pcs become 2 pcs, sugar 200 g becomes 100 g

Batch cooking (2 to 8): Rice 150 g becomes 600 g, chicken 250 g becomes 1000 g, soy sauce 2 tbsp becomes 8 tbsp

Solo breakfast (4 to 1): Oats 200 g becomes 50 g, milk 400 ml becomes 100 ml, honey 4 tsp becomes 1 tsp

Odd scaling (6 to 5): Butter 120 g becomes 100 g, flour 360 g becomes 300 g, factor = 0.833x

FAQ - Frequently asked questions

Does scaling work for baking recipes?

Scaling works perfectly for ingredient quantities, but baking has one catch: oven time and temperature do not scale linearly. Doubling a cake batter means you need a larger pan (or two pans), and bake time changes. The calculator handles the ingredient math - adjust bake time separately based on pan size and visual cues.

What about eggs? You cannot use 1.75 eggs.

The calculator gives you the exact mathematical result. For eggs, round to the nearest whole number. 1.75 eggs means use 2 eggs. If scaling down gives you 0.5 eggs, beat one egg and use half. For precision baking, weigh the beaten egg and use the fraction by weight (one large egg weighs about 50 g).

Can I scale a recipe by weight if servings are not listed?

Yes. If the recipe does not list servings, use total yield instead. A bread recipe that makes 1 loaf (800 g) and you want 2 loaves: set original to 1, target to 2. The factor is 2.0x regardless of whether you call it "servings" or "loaves" or "batches".

Do spices and seasonings scale the same way?

Mathematically yes, but in practice salt, chili and strong spices should be scaled more conservatively. A good rule: scale spices by about 75-80% of the factor, then taste and adjust. Doubling a recipe? Use 1.5x the spices instead of 2x. Tripling? Use 2.5x instead of 3x.

What units does the calculator support?

Nine common kitchen units: grams, kilograms, milliliters, liters, tablespoon, teaspoon, cup (250 ml), pieces and pinch. The unit carries through unchanged - if you enter grams, the result stays in grams. The calculator does not convert between units (use the Kitchen Measurement Converter for that).

How many ingredients can I enter at once?

Up to 10 ingredients per calculation. For recipes with more ingredients, run the calculator twice - the factor stays the same, so results are consistent.

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