Recipe Scaling Calculator
Scale a recipe up or down for a different number of servings.
Please note: Cooking guides only. Times and temperatures vary with oven calibration, altitude, starting temperature and cut. For anything where safety matters — poultry, pork, sous vide, preserving — use a probe thermometer and follow your national food safety guidance rather than a calculated time.
What the Recipe Scaling Calculator does
Scaling a recipe multiplies every ingredient by the ratio of target to original servings. That works cleanly for the ingredients themselves, but seasoning, leavening and cooking times follow their own rules — which is why a scaled recipe still needs tasting.
Formula
Factor = Target servings ÷ Original servingsNew quantity = Original quantity × Factor
Inputs explained
| Input | Unit | Required | Notes |
|---|---|---|---|
| Original servings | number | Yes | Accepts more than 0. |
| Servings you want | number | Yes | Accepts more than 0. |
| Ingredient names | text | Yes | Separate with commas or new lines. |
| Quantities | text | Yes | One number per ingredient, in the same order. |
| Units | text | Optional | Optional. One per ingredient — purely a label, not converted. |
How to use it
- Enter Original servings, Servings you want, Ingredient names and Quantities.
- Optionally add Units.
- Select Calculate.
Worked example
A recipe for 4 people scaled to 6.
- Original
- 4
- Target
- 6
- Ingredients
- Flour 250 g, Butter 125 g, Eggs 2
The factor is 1.5, so 250 g flour becomes 375 g, 125 g butter becomes 187.5 g, and 2 eggs becomes 3.
Frequently asked questions
Does baking time scale with the recipe?
No. A doubled cake in a larger tin takes longer but nowhere near twice as long — depth matters more than volume. Check for doneness from the original time onwards.
What do I do about half an egg?
Beat a whole egg, weigh it, and use half. A large egg is about 50 g out of shell, so 25 g is a fair half.
Should I scale salt and spices linearly?
Start at about 75% of the scaled amount and adjust by taste. Seasoning perception does not rise in proportion to volume, and it is far easier to add than remove.
Method and sources
Method. Every ingredient is multiplied by the ratio of target servings to original servings.
Assumptions
- The original recipe is balanced, and each ingredient scales linearly with yield.
Limitations
- Cooking time and temperature do not scale with quantity. A doubled tray is deeper, not wider, and needs longer at the same temperature — the calculator scales ingredients only.
- Several ingredients do not scale linearly in practice: salt, leavening, spice and alcohol reduction all need judgement at large multiples.
- Pan size, evaporation rate and equipment capacity all constrain how far a recipe can be scaled at all.
Sources
- None — this is a ratio applied to the reader's own recipe — Not applicable. Stated explicitly so the absence of a citation is not read as an omission: the calculation is arithmetic and makes no food-safety claim.