How scaling works
The scale factor is the target servings divided by the original servings — doubling a 4-serving recipe to 8 servings gives a factor of 2, and halving it to 2 servings gives a factor of 0.5. Every ingredient quantity is multiplied by that same factor, so the ratios in the recipe stay exactly the same.
Why quantities are shown as fractions
Baking recipes are full of fractions — a third of a cup, an eighth of a teaspoon — and multiplying them by an odd factor like 1.5 often lands on another common fraction rather than a clean decimal. This tool snaps scaled results back to the nearest common fraction (halves, thirds, quarters, eighths) when they're close enough, so you get "1 ⅓ cups" instead of "1.333333 cups".
What doesn't scale linearly
Ingredient quantities scale directly, but a few things don't: baking and cooking times change more slowly than volume (a bigger pan needs proportionally less extra time), pan size needs to increase to match a larger batch, and strong flavorings like salt, chili or spices are often best scaled a little more conservatively than the rest of the recipe, then adjusted to taste.
Frequently asked questions
Can I enter fractions like 1/2 or 1 1/2 cups?
Yes. Enter simple fractions as 1/2 or 3/4, and mixed numbers as 1 1/2. The scaled result is shown as a clean fraction too, when it lands close to a common one like a quarter, third or half.
Does scaling a recipe also scale the cooking time?
No, this tool only scales ingredient quantities. Cooking and baking times don't scale linearly, especially for baked goods, so check doneness visually or with a thermometer rather than simply multiplying the original time.
How do I scale a recipe up or down?
Multiply every ingredient by the same factor. To double it, ×2; to make 6 servings from 4, ×1.5. The tool does this for the whole list.
Do cooking times change when I scale a recipe?
Less than the quantities do. A bigger batch may need a little longer, but temperatures stay the same; check for doneness rather than just multiplying the time.
How do I halve an egg?
Beat one egg and use about half by volume (roughly 25 g), or adjust the recipe to avoid odd amounts.