Recipe Scaler
Scale a recipe up or down between serving sizes: get the multiplier and the converted quantity for any ingredient, plus what to watch when scaling.
Comment utiliser cette calculatrice
- 1Enter how many servings the recipe currently makes.
- 2Enter how many servings you want.
- 3Enter one ingredient's amount to see its scaled quantity.
- 4Apply the same scale factor to every other ingredient, then adjust time and seasoning by taste.
Comment ça marche
Recipe scaling
scale factor = desired servings ÷ original servings new amount = original amount × scale factor apply the same factor to every ingredient time, pan size, and seasoning scale non-linearly
Scaling a recipe is proportional reasoning applied to cooking. Divide the number of servings you want by the number the recipe makes to get a single scale factor, then multiply every ingredient quantity by that factor. Halving a recipe uses a factor of 0.5; making one and a half times as much uses 1.5; tripling uses 3. Because every ingredient is multiplied by the same number, their ratios to one another are preserved, which is what keeps the dish balanced. This works cleanly for the bulk ingredients — flour, liquids, sugar, protein — but several elements of a recipe are governed by physics and chemistry rather than simple proportion, and those need separate judgement rather than blind multiplication.
Exemple détaillé
To turn a recipe that serves 4 into one that serves 6, the scale factor is 6 ÷ 4 = 1.5. An ingredient calling for 2 cups becomes 2 × 1.5 = 3 cups, and every other quantity is multiplied by 1.5 as well — so 1 teaspoon of an ingredient becomes 1.5, and 250 g becomes 375 g.
Recipe Scaler : le guide complet
The one factor that does all the work
Scaling a recipe sounds fiddly but rests on a single number: the ratio of the servings you want to the servings the recipe makes. Once you have that scale factor, every ingredient is just multiplied by it. This is far more reliable than trying to reason about each ingredient separately, because it guarantees the proportions stay identical — the ratio of flour to sugar to butter that makes the recipe work is untouched when they are all multiplied by the same amount.
The factor also handles awkward serving conversions gracefully. Turning a recipe for 6 into one for 4 is a factor of 0.667, and multiplying each ingredient by that gives the right smaller quantities even when they come out as odd fractions. The mental shortcut of 'add half again' for 1.5× or 'take half' for 0.5× works for the easy cases, but a computed factor is what lets you scale to any serving count, including the non-round ones that real cooking throws up.
What doesn't scale linearly
Multiplying every ingredient by the scale factor keeps the recipe balanced, but a recipe is more than a list of ingredients, and several of its other elements refuse to scale in a straight line. The most important is cooking time and vessel size. Doubling a cake batter does not mean doubling the baking time; it means using a larger pan, and the bake time changes in a way that depends on the new depth and surface area, not on the quantity. Cram a doubled batter into the same pan and it will overflow or cook unevenly.
Seasoning is the other classic trap. Salt, strong spices, and aromatics often do not need to be doubled when a recipe is doubled — the perception of these flavours is not strictly proportional to quantity, and scaling them literally can produce an over-seasoned dish. Experienced cooks scale the bulk ingredients by the factor but add salt and spice more cautiously, tasting as they go. Leavening agents like baking powder and yeast can behave non-linearly too, sometimes needing slightly less than a straight multiple in large batches.
Scaling with confidence
The safest approach is to treat the computed quantities as a precise starting point for the ingredients that scale — the flours, liquids, sugars, fats, and proteins that form the body of the dish — and to treat the non-linear elements as things to adjust by judgement. Scale the structure exactly, then handle time, temperature, pan size, and seasoning with a cook's attention rather than a calculator's arithmetic. This combination of exact proportions and adjusted technique is how professional kitchens scale recipes reliably from a few covers to a few hundred.
It also helps to convert to weight when scaling significantly. Volume measures like cups are imprecise and the errors compound when multiplied, whereas weighing ingredients keeps a scaled recipe accurate. Many bakers work in grams precisely so that scaling is a clean multiplication with no rounding drift. Whatever the units, the discipline is the same: let the scale factor set the quantities, keep the ratios intact, and reserve your own judgement for the parts of cooking that a multiplier cannot capture.
Questions fréquentes
How do I scale a recipe?
Divide the servings you want by the servings the recipe makes to get a scale factor, then multiply every ingredient by it. To take a recipe for 4 up to 6, the factor is 1.5, so 2 cups becomes 3 cups and every other amount is multiplied by 1.5 as well.
Do I double the cooking time when I double a recipe?
No. Cooking time doesn't scale with quantity — it depends on the pan size and the depth of food. A doubled cake needs a larger pan and a modestly longer bake, not double the time. Scale the ingredients by the factor, but adjust time and temperature by judgement.
Should I double the salt and spices too?
Be cautious. Salt, strong spices, and aromatics often don't need a full doubling, because their perceived intensity isn't strictly proportional to quantity. Scale the bulk ingredients exactly, then add seasoning more conservatively and taste as you go, especially when scaling up.
Is it better to scale by weight or volume?
By weight when scaling significantly. Volume measures like cups are imprecise, and the errors multiply when scaled, so weighing keeps the recipe accurate. Many bakers work in grams precisely so that scaling is a clean multiplication without rounding drift.