Recipe Scaler

Why Recipe Scaling Is Not Just Multiplication

Recipe scaling looks simple on paper: multiply every ingredient by the ratio between the new serving size and the original serving size. In practice, kitchens rely on a mix of weights, volumes, and “whole item” counts. This calculator handles the math while keeping your units intact, so a cup stays a cup and a gram stays a gram. If you choose fraction mode, the tool converts decimals into common kitchen fractions like 1/2, 1/3, 2/3, and 3/4 to make measuring faster and more realistic.

Scaling becomes more important when you change the batch size drastically. Large increases can amplify rounding errors, so using weights (grams or ounces) produces the most repeatable results. For instance, scaling a cookie recipe from 4 servings to 10 servings yields a factor of 2.5. That means 0.75 cups of sugar becomes 1.875 cups, which is hard to measure precisely. Fraction output helps by converting to 1 7/8 cups. In a professional kitchen you might switch to grams for even more accuracy.

Some ingredients scale linearly, and others need judgment. Spices, leaveners, and salt can become more intense at larger batch sizes because flavor perception changes with volume. This calculator intentionally keeps the math transparent; it shows the scaled amounts so you can apply culinary judgment and adjust to taste. It also avoids automatic unit conversions to prevent surprises. You stay in control of whether you measure in cups, tablespoons, or grams.

Use the output as your baseline, then taste and test. If you are scaling down a recipe, keep an eye on cooking time and bakeware size, and consider the Cake Pan Converter for volume changes. For scaling up, note that cooking times rarely double; surface area and heat transfer matter more than sheer volume. With consistent scaling, you can confidently prepare small batches, family-size dinners, or large event catering with the same core recipe.

Formula

Scale factor: F = servings_target / servings_original.

Scaled ingredient: amount_new = amount_original × F.

Example Calculation

Original recipe: 4 servings, 2 cups of flour. Target: 10 servings. The scale factor is 10 / 4 = 2.5. The new flour amount is 2 × 2.5 = 5 cups. In fraction mode, 0.75 cups of sugar becomes 1 7/8 cups.

FAQs

Why do I get awkward fractions?

Real recipes often scale to irregular amounts. Fraction mode rounds to common kitchen measures.

Should I switch to grams?

Yes, weight-based recipes are more accurate when scaling big batches.

Does this tool change units?

No, it keeps the unit you enter so you stay consistent with your recipe.

Is this calculator private?

Yes. All calculations run locally in your browser.

How it works

This recipe scaler multiplies each ingredient by the serving ratio and optionally formats decimals into kitchen fractions. All computation is client-side for privacy.