Recipe Scaling Calculator
Scaling a recipe means multiplying every ingredient by the ratio between the servings you want and the servings the recipe was written for. Do it by hand and a single missed decimal ruins the dish; this calculator applies the ratio precisely to each amount you enter, so a recipe for four becomes a reliable recipe for two or for forty.
Enter the original number of servings, the number you want to make, and the amount of one ingredient in the original recipe. The calculator returns the scaled amount and the overall scaling factor, which you can then apply to every other ingredient on the list. It works for any unit — grams, cups, spoons — because it scales the number, not the unit.
It is the difference between a recipe that travels and one that does not — the same dish that works for four dinner guests can be made to work for a crowd or scaled down to a solo supper, without re-developing the whole thing from scratch.
Enter your values to see the result.
How this is calculated
The scaling factor is the desired number of servings divided by the original number of servings. Every ingredient amount is multiplied by that factor, so a recipe written for four servings made for six uses a factor of 6 ÷ 4 = 1.5, and every amount is increased by half. The unit is unchanged — grams stay grams, cups stay cups — because only the number is scaled.
The model assumes the recipe scales linearly, which holds well for soups, sauces, stews and most savoury cooking where the ratio of ingredients is what matters. It does not hold perfectly for baking, where leavening, pan size and oven behaviour interact with scale: a cake batter doubled does not always bake in twice the time at the same temperature, and yeast doughs behave differently in very large or very small batches.
For seasonings, salt and spices, linear scaling can over-season at large scales and under-season at small ones, because perception of salt and heat is not strictly proportional. Experienced cooks scale salt and spice by taste rather than by the raw factor, especially when scaling up by more than double. Use the factor as a precise starting point, then adjust seasoning to taste.
Worked example
A recipe for 4 servings calls for 200 g of flour. You want to make 6 servings.
- 1Factor = 6 ÷ 4 = 1.5.
- 2Scaled flour = 200 × 1.5 = 300 g.
- 3Every other ingredient is multiplied by 1.5 the same way: 1 tsp becomes 1.5 tsp, 2 eggs become 3 eggs.
- 4For a half batch (2 servings), the factor is 2 ÷ 4 = 0.5, so 200 g becomes 100 g.
Frequently asked questions
- Can I scale by a factor instead of servings?
- Yes — set the original servings to 1 and the desired servings to your factor (for example 1.5 for a 50% larger batch). The scaled amount is the ingredient amount multiplied by that factor.
- Does scaling work for baking?
- For yeast doughs and cakes it works well up to roughly double or half. Very large or very small batches change oven behaviour, mixing time and pan depth, so expect to adjust baking time and temperature rather than scaling indefinitely.
- Should I round the scaled amount?
- The calculator shows the exact scaled value. For cooking, round to the nearest sensible measure (a quarter teaspoon, 10 g). For baking, keep the precision — small errors compound across many ingredients.
- How do I scale eggs when the factor gives a fraction?
- Round to the nearest whole egg for casual cooking, or beat the eggs and measure by weight or volume for baking precision (one large egg is about 50 g or roughly 3 tablespoons). For a factor of 1.5 on 2 eggs, use 3 eggs; for 0.5 on 3 eggs, use 1 whole egg plus 1 yolk or white as the recipe needs.
- Does cooking time scale with the recipe?
- No — cooking time depends on the depth and mass of the food in the pan, not on the total quantity. A doubled sauce in the same pan takes longer to reduce; a doubled cake in two tins takes the same time as one. Adjust time by watching the food, not by scaling the recipe’s time.
Related calculators
Method: linear scaling by the ratio of desired to original servings. No external data source. Last updated: September 2026.
These results are general estimates from established formulas and conversion factors. Paint coverage, tile yields, concrete volumes, fuel economy, oven behaviour and clothing and shoe sizes vary by product, surface, vehicle, oven and brand. Always confirm with your supplier, the product label or the brand’s own size chart before buying or acting on a calculation.