Food Scale Calculator

Data Source and Methodology

This calculator provides precise conversions based on internationally recognized standards. All calculations are performed using these authoritative sources:

• Weight Conversions: Based on the avoirdupois pound definition from the NIST Handbook 44 (2024 Edition), Appendix C. Specifically, 1 pound (lb) is exactly 0.45359237 kilograms (kg).
• Volume Conversions: Based on the legal definitions for cooking measurements in the United States, as defined by 21 U.S. Code § 321a.
  • 1 Tablespoon (tbsp) = 15 milliliters (ml)
  • 1 Teaspoon (tsp) = 5 milliliters (ml)
  • 1 US Fluid Ounce (fl oz) = 29.5735 ml
  • 1 US Cup = 8 US fl oz = 236.588 ml

All calculations are based strictly on the formulas and data provided by these sources. Note that conversions between weight (e.g., grams) and volume (e.g., cups) are not possible without knowing the specific ingredient's density. This tool only converts between compatible unit types (weight-to-weight and volume-to-volume).

The Formulas Explained

The calculator uses two primary sets of formulas for its operations.

1. Recipe Scaling Formulas

To scale a recipe, the tool first determines a Scaling Factor and then applies it to your original amount.

If scaling "By Factor": The formula is a direct multiplication.

If scaling "By Portions": The calculator first finds the scaling factor from your portion sizes.

It then applies this factor to the original amount as shown in the first formula.

2. Unit Conversion Formulas

Conversions are done by first converting the input value to a standard base unit (grams for weight, milliliters for volume) and then converting from that base unit to the target unit.

Example (Weight): To convert Ounces (oz) to Pounds (lb):

Example (Volume): To convert US Cups to Teaspoons (tsp):

Glossary of Variables

Original Amount

The starting quantity of your ingredient (e.g., 100).

Original Unit

The unit of measure for your original amount (e.g., Grams).

Scaling Factor

The multiplier you wish to apply to your recipe (e.g., 1.5 to increase by 50%, 0.5 to halve).

Original Portions

The number of servings the original recipe yields (e.g., 4).

Desired Portions

The number of servings you want to make (e.g., 6).

Scaled Amount

The calculated new amount for your ingredient after scaling.

Converted Amount

The calculated amount after converting from one unit to another.

How It Works: A Step-by-Step Example

Let's say you have a bread recipe that calls for 500g of flour and serves 4 people, but you need to make enough for 6 people.

1. Select the "Recipe Scaler" tab.
2. In the "Original Ingredient" section, enter 500 in the "Original Amount" field and select Grams (g) from the "Unit" dropdown.
3. In the "Scaling Method" section, select "By Portions".
4. The portion inputs appear. Enter 4 for "Original Portions" and 6 for "Desired Portions".
5. The calculator instantly displays the result in the "Scaled Amount" box.

Calculation Breakdown:

• $\text{Scaling Factor} = 6 \text{ (Desired)} / 4 \text{ (Original)} = 1.5$
• $\text{New Amount} = 500\text{g} \times 1.5 = 750\text{g}$

The result will show 750.00 g, which is the new amount of flour you need.

Frequently Asked Questions (FAQ)