Enter how many servings the recipe was written for, how many you actually need, and the amount of one ingredient. This tool works out the scaling factor and the new amount for that ingredient, so you can repeat the same factor for every line in the recipe.
Scaled amount3
Scaling factor1.5×
How this calculation works
The scaling factor is simply the servings you want divided by the servings the recipe makes: factor = desired servings ÷ original servings. A recipe for 4 scaled to 6 servings has a factor of 1.5.
Every ingredient amount is multiplied by that same factor to get the new amount: scaled quantity = original quantity × factor. Enter one ingredient at a time (for example, 2 cups of flour) to see its scaled amount, then apply the same factor to the rest of the recipe.
Because the factor is fixed once you know the two serving counts, you can reuse it mentally for the whole ingredient list without re-entering the servings each time.
Worked example
A recipe serves 4 and you need it for 6 people. The factor is 6 ÷ 4 = 1.5. If the recipe calls for 2 cups of flour, the scaled amount is 2 × 1.5 = 3 cups. Apply the same 1.5× factor to every other ingredient — 1 cup of sugar becomes 1.5 cups, 2 eggs becomes 3 eggs, and so on.
What scales linearly and what doesn't
Most of a recipe's ingredients scale in direct proportion to servings, but a handful of categories behave differently and deserve a second look before you multiply blindly:
Ingredient type
Scales linearly?
Tip
Flour, liquids, sugar
Yes
Multiply by the factor directly.
Vegetables, proteins
Yes
Multiply by the factor directly.
Salt and strong spices
Partially
Scale by about 75–90% of the factor, then taste and adjust.
Baking powder / baking soda
Partially
Large scale-ups often need less than the full multiple — start conservative.
Yeast
Partially
Doubling dough rarely needs double the yeast; rise time matters more than exact quantity.
Cook / bake time
No
Depends on thickness and pan size — use a thermometer or doneness test instead.
Pan / dish size
No
Keep batter depth similar to the original; adjust temperature or time if depth changes.
Rounding to practical kitchen measures
Most measuring cups and spoons step in 1/8-cup, 1/4-teaspoon, or 1-tablespoon increments — round your scaled result to the nearest one rather than keeping several decimal places.
For small amounts (a pinch, a dash), rounding up slightly is usually safer than rounding down to near-zero.
For eggs and other whole items, round to the nearest whole number and adjust liquid slightly if you rounded down, or add a splash of extra liquid if you rounded up.
When a scaled amount lands awkwardly (like 0.83 cup), converting to tablespoons (0.83 cup ≈ 13 Tbsp) can be easier to measure than a fractional cup.
Common fraction-to-decimal conversions
Recipes are often written in fractions. Converting to decimals first makes scaling by any factor straightforward:
Fraction
Decimal
1/8
0.125
1/4
0.25
1/3
0.333
1/2
0.5
2/3
0.667
3/4
0.75
Frequently asked questions
Does everything in a recipe scale by the same factor?
Most ingredients do — flour, liquids, sugar, most vegetables and proteins scale linearly. A few things do not: salt and strong spices often taste better scaled by less than the full factor (start around 75% of the factor and adjust to taste), and leavening agents like baking powder or yeast do not always need the full multiple, especially at large scale-ups.
Does cook time scale the same way as ingredients?
No. Cook time depends on the thickness and mass of the food, not a simple multiplier. Doubling a cake recipe in a bigger pan of the same depth usually needs only a few extra minutes, while doubling it in a much deeper pan can need significantly longer. Use a thermometer or doneness test rather than scaling the time by the same factor.
What if scaling up changes my pan size?
Try to keep the batter or filling depth similar to the original recipe. If you must use a larger pan, the cook time usually drops a little (thinner layer, more surface area); a smaller, deeper pan usually needs longer at a slightly lower temperature so the inside cooks before the outside overbrowns.
How do I scale awkward fractions like 2/3 cup?
Convert to a decimal first (2/3 cup ≈ 0.667 cup), multiply by the factor, then round to the nearest practical measure — most kitchen tools measure in 1/8-cup or 1-tablespoon increments, so round to the closest one rather than using a hyper-precise decimal.
Can I scale a recipe down as well as up?
Yes — enter a smaller desired-servings number than the original and the factor will be below 1. The same caution about salt, spices, and leavening applies in reverse: very small scaled amounts (like a pinch of baking soda) are hard to measure precisely and may need rounding up slightly rather than down.
Why does my scaled recipe taste different even though the math is right?
Scaling assumes every ingredient behaves linearly, but cooking chemistry does not always agree. Reductions, caramelization, and evaporation depend on surface area and time, not just quantity, so a heavily scaled-up sauce may need extra simmering time to reduce properly even though the ingredient amounts are mathematically correct.
Does this tool store my recipe or ingredient data?
No. The calculation runs entirely in your browser and nothing you enter is uploaded, logged, or saved anywhere.