Recipe scaling calculator
Enter what the recipe makes and what you need, then an ingredient amount, to get the adjusted quantity in measurements you can actually use.
Use this many cups
2.250
1.5000 times the original 1.5 cups
How to use it
- Enter how many servings the recipe is written for and how many you want.
- Enter an ingredient's amount and its unit. Use decimals for fractions: 0.75 for ¾.
- Read the scaled amount, and the cups-tablespoons-teaspoons row for volume measures.
- Repeat for each ingredient; the scale factor stays the same.
Worked example
A recipe for 4 needs 1½ cups of flour and you’re cooking for 6.
Scale factor is 6 ÷ 4 = 1.5. Flour becomes 1.5 × 1.5 = 2.25 cups, which is 2 cups + 4 tablespoons.
How this is calculated
The scale factor is servings wanted ÷ servings the recipe makes, and the new amount is the original amount × that factor. Volume amounts are also broken into cups, tablespoons and teaspoons: 1 cup = 16 tablespoons = 48 teaspoons. Pan size, oven temperature and cooking time don't scale with the factor, and leavening, salt and spices rarely scale linearly either, so start with a little less of those and taste.
scale factor = servings wanted ÷ servings the recipe makes
new amount = original amount × scale factor
Volume amounts are also broken into cups, tablespoons and teaspoons: 1 cup = 16 tablespoons = 48 teaspoons. Pan size, oven temperature and cooking time don’t scale with the factor; see the FAQ.
Rates, sources and limits
Last reviewed 13 Sep 2026 by the CalcRabbit team. Estimates only, not financial, tax or medical advice.
Frequently asked questions
Does cooking time scale too?
No. A double batch in the same pan is thicker and takes longer; split across two pans it takes about the same time. Check for doneness rather than doubling the minutes. Oven temperature never changes.
What about baking powder, salt and spices?
Scale them, then hold back a little when the factor is large. Leavening especially doesn't need to double when the batch doubles, because the pan's surface area matters more than the volume. Taste and adjust where you can.
How do I scale eggs?
Round to the nearest whole egg for factors near 1. For odd fractions, beat an egg and use part of it by weight: a large egg is about 50 g, so half an egg is 25 g.
Which pan do I use for a bigger batch?
Match the area, not the diameter. A 9-inch round pan is 64 square inches; a 13 × 9 pan is 117, almost double. Going from an 8-inch to a 9-inch round pan adds about 27%.