Calculateus

Recipe Scaler

Scale a recipe up or down to a new number of servings, converting every ingredient amount proportionally.

Result

Scaled Amount
2 cup
Scale Factor
×2
New Servings
8

Repeat this for each ingredient in the recipe using the same scale factor.

About the Recipe Scaler

Doubling a recipe, or cutting it down to serve two instead of six, means scaling every single ingredient by the same factor - easy in concept, error-prone in practice once fractions get involved.

How It Works

The calculator divides your desired number of servings by the original recipe's servings to find a single scale factor, then multiplies your ingredient amount by that factor. The same scale factor applies to every ingredient in the recipe.

scale factor = desired servings ÷ original servings; scaled amount = original amount × scale factor

Examples

Halving a recipe

A recipe for 4 servings scaled to 2 servings gives a scale factor of 0.5 - every ingredient amount is simply cut in half.

Scaling for a party

A recipe for 6 servings scaled to 20 servings gives a scale factor of about 3.33 - so 2 cups of an ingredient becomes about 6.67 cups.

Advantages

  • Calculates one scale factor that applies to every ingredient in the recipe
  • Works for scaling up or down
  • Shows the exact new servings count alongside the scaled amount

Common Mistakes

  • Scaling only some ingredients and forgetting others
  • Applying the full scale factor to leavening agents and strong spices without adjusting to taste
  • Not adjusting pan size or bake time when significantly scaling a baked recipe

Edge Cases to Watch For

  • Leavening agents (baking soda, baking powder, yeast) and strong spices often don't scale perfectly linearly - when more than doubling or halving, many bakers use slightly less than the full factor for these specific ingredients.
  • Pan size and bake time don't scale the same way ingredients do - doubling a cake recipe usually means a bigger pan or multiple pans, not just twice the batter in the same pan.
  • Cooking and baking times generally scale less than proportionally with quantity - a doubled batch rarely needs exactly double the time.

Common Use Cases

  • Doubling a weeknight recipe to have leftovers
  • Scaling a recipe down for a smaller household
  • Scaling a recipe up for a party or potluck
Written & fact-checked by the Calculateus TeamLast updated August 5, 2026How we verify our formulas

Frequently asked questions

Do I need to run this for every ingredient separately?

Yes for the amount field, but the scale factor (desired servings ÷ original servings) is the same for every ingredient in the recipe - once you know it, you can multiply each ingredient amount by that factor directly.

Does scaling work perfectly for baking?

For most ingredients yes, but leavening agents (baking soda, baking powder, yeast) and spices don't always scale linearly - when more than doubling or halving a baked recipe, many bakers scale those specific ingredients slightly less than the full factor to avoid an overly strong or unstable result.

Related calculators

Ingredient ConverterConvert cooking ingredients between cups, grams, tablespoons and ounces using real ingredient density, not a generic volume-to-weight guess.Oven Temperature ConverterConvert oven temperature between Fahrenheit, Celsius, and UK Gas Mark for any recipe.Air Fryer ConverterConvert a conventional oven recipe's temperature and cook time to air fryer settings.Baking Pan ConverterConvert a recipe from one baking pan size to another using each pan's surface area.

Conclusion

Once you know the scale factor, scaling a whole recipe is just repeated multiplication - the hard part is doing that consistently across every ingredient without a calculator. Run each ingredient through with the same original and desired servings to keep the whole recipe proportional.