Cooking Calculators
Recipe Scaler
Scale ordered ingredient rows from original to desired servings using decimals or ASCII fractions while preserving entered units.
Enter the values and review the result.
Servings and ordered ingredients
The initial row is structural and ignored while completely blank. A partly entered row must include both name and quantity.
Ingredient rows
1 of 20 structural rows
Accepted quantities: whole number, decimal, a/b, or w a/b with exactly one ordinary space. Text, ranges, signs, Unicode fractions, and whitespace-padded values are rejected.
Enter servings and at least one complete ingredient row.
Proportional servings model
The scale factor equals desired servings divided by original servings. Every active ingredient quantity is multiplied independently by that same factor, without intermediate rounding. Rows remain in entered order and duplicate ingredient names are allowed.
Servings are strict whole numbers from 1 through 100000. Ingredient quantities can be whole numbers, ASCII decimals, simple fractions such as 3/2, or mixed numbers such as 1 1/2. Fractions are parsed for arithmetic, while output is deterministic decimal text with up to six places.
Worked example
An illustrative recipe makes 4 servings and is scaled to 10, so the factor is 10 / 4 = 2.5. Enter Flour as 2 cups, Salt as 1/2 tsp, and Eggs as 3 with no unit.
Flour: 2 × 2.5 = 5, producing 5 cups Flour.
Salt: 1/2 × 2.5 = 1.25, producing 1.25 tsp Salt.
Eggs: 3 × 2.5 = 7.5, producing 7.5 Eggs.
Raw copy contains exactly those three ordered lines, separated internally by LF with no summary or trailing newline.
Rows, units, and validation
A completely blank row is ignored. Once any field is entered, name and quantity are required; unit remains optional. Accepted name and unit text is preserved rather than trimmed or normalized. Tabs, line breaks, control characters, whitespace-only text, partial rows, and unsupported quantity notation produce textual validation with no partial output.
Unit text is descriptive only. The scaler does not know whether “cup,” “g,” “tsp,” or another entry is appropriate, and it does not convert between them or apply ingredient density. Use the Cooking Converter separately when a compatible volume, mass, or temperature conversion is needed.
Assumptions and culinary limitations
This is proportional arithmetic based entirely on the values you enter. Seasoning, salt, leavening, vessel size, batch depth, mixing, cooking time, temperature, texture, and practical yield may not scale linearly. Some ingredients are commonly counted rather than divided, but the calculator does not choose a rounding or preparation rule for you.
The output is not recipe generation, culinary advice, food-safety advice, allergen advice, nutrition analysis, or a guarantee of a finished result. Check the original recipe, suitable equipment, ingredient handling, and authoritative safety guidance independently.
Quick answers
What this calculator answers
- Scaling model: Every active ingredient quantity is multiplied by desired servings divided by original servings.
- Unit boundary: Unit text is preserved exactly as entered; scaling never converts cups, grams, teaspoons, or other units.
Transparency note
Accuracy and limitations
Calzivo tools are built for practical estimates, conversions, and checks. Some tools use standard formulas or simplified assumptions, and results can be affected by input accuracy, rounding, units, local rules, or changing official requirements.
Results depend on the values you enter and any simplified assumptions used by the tool. Verify important results before making decisions or submitting official information.
How to Use This Tool
Use these steps to enter the right inputs and interpret the result correctly.
Enter whole-number original and desired servings from 1 through 100000.
Enter at least one ingredient name and quantity; unit text is optional.
Add up to 20 rows. Use strict decimals, simple fractions, or mixed numbers.
Scale the ordered rows and copy only the decimal output block.
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Related Guides
Background reading and explanations related to Recipe Scaler.
Frequently Asked Questions
Common questions about Recipe Scaler and how to read the result.
Which quantity forms are accepted?
Use whole numbers, ASCII decimals, simple fractions such as 1/2, or mixed numbers such as 1 1/2. Unicode fractions, ranges, and prose quantities are rejected.
Does the scaler convert units?
No. Unit text is preserved exactly and is never interpreted. Use Cooking Converter separately for compatible unit conversion.
Do all recipe details scale linearly?
No. Seasoning, leavening, vessel size, cooking time, temperature, texture, and practical yield may need recipe-specific judgment.
Why is output shown as decimals?
Decimal-only output avoids silently approximating a result to a convenient fraction. Up to six decimal places are shown.