Recipe Scaler Calculator
Convert recipe scaler with our free cooking calculator. Get accurate measurements, scaling, and recipe adjustments instantly.
Reviewed by Daniel Agrici, Founder & Lead Developer
Formula
Scaled Amount = Original Amount × (Desired Servings ÷ Original Servings)
Calculate the scaling factor by dividing the desired number of servings by the original. Then multiply each ingredient amount by this factor. A factor greater than 1 scales up, less than 1 scales down, and exactly 1 keeps amounts unchanged.
Worked Examples
Example 1: Doubling a Family Recipe
Problem:A cookie recipe serves 24 and you need 48 cookies. The recipe calls for 2 cups flour, 1 cup sugar, and 2 eggs.
Solution:Scaling factor = 48 / 24 = 2.0\nFlour: 2 × 2.0 = 4 cups\nSugar: 1 × 2.0 = 2 cups\nEggs: 2 × 2.0 = 4 eggs
Result:Scaling factor: 2x | Flour: 4 cups | Sugar: 2 cups | Eggs: 4
Example 2: Halving a Party Recipe
Problem:A punch recipe serves 20 guests but only 8 are coming. It calls for 5 cups juice and 2 cups soda.
Solution:Scaling factor = 8 / 20 = 0.4\nJuice: 5 × 0.4 = 2 cups\nSoda: 2 × 0.4 = 0.8 cups
Result:Scaling factor: 0.4x | Juice: 2 cups | Soda: 0.8 cups
Frequently Asked Questions
How do I scale a recipe up or down accurately?
To scale a recipe, divide the desired number of servings by the original number of servings to get the scaling factor. Then multiply every ingredient amount by this factor. For example, if a recipe serves 4 and you want to serve 10, the scaling factor is 10/4 = 2.5. An ingredient originally at 2 cups becomes 2 × 2.5 = 5 cups. While this works perfectly for most ingredients, some items like spices, leavening agents (baking powder/soda), and salt should be scaled more conservatively — typically at 75-80% of the calculated amount — and adjusted to taste.
Should I scale cooking time when I scale a recipe?
Cooking time does not scale linearly with recipe size. If you double a recipe, you do not double the cooking time. For stovetop cooking, larger batches may need 25-50% more time due to increased volume taking longer to heat through. For baking, use the same temperature but check doneness earlier — a doubled cake recipe in a larger pan may only need 10-15 extra minutes. The best approach is to use internal temperature or visual doneness cues rather than relying solely on time. Dividing a recipe into the original-sized portions and cooking in batches gives the most reliable results.
References
Reviewed by Daniel Agrici, Founder & Lead Developer · Editorial policy