The most frequent measurements made in the home are those used for cooking and baking. Metric "cup and spoon" measures are only slightly larger than, and can often be used interchangeably with, the customary "cup and spoon" measures. There are only a few ingredients that are not measured by weight (pounds and ounces) that will be expressed differently in metric recipes
Cooking Measurement Tips
Select the right cooking tool for the job. Use that tool as designed to get the best measurement result. Using dry measuring cup (designed to measure the volume of dry commodities like sugar) instead of using a fluid measuring cup (designed to measure the volume of liquid commodities like water) is a common way of introducing measurement errors into the cooking process.
Use good measurement techniques when reading a meniscus of a fluid measuring cup, which have a large surface area. Set the fluid measuring cup on a level surface to accurately read the meniscus and read the meniscus at eye level. Tips on reading a meniscus are available
Strike off excess dry ingredients when using a dry measuring cup.
Measuring ingredients by mass (weight) using an appropriate kitchen scale is a best practice to improve recipe accuracy, rather than measuring ingredients by volume using fluid and dry measuring cups.
It’s important to note that there are two types of U.S. customary volume measurement units (e.g., liquid and dry). For example, fluid ounce (fl oz) and the Avoirdupois ounce (oz). This contrasts with metric volume (e.g., liter, milliliter), which is suitable for measuring both fluid and dry volume. Because much of metric cooking uses mass (weight), the density of different ingredients can be important. NIST SP 430, Household Weights and Measures, provides the approximate weight of several commodities appropriate for home cooking applications.
Have you found a delicious international recipe or a heritage recipe in need of conversion? An online cooking calculator or smartphone app can help you can convert measurement units like pounds to grams, gallons to liters, and degree Fahrenheit to degree Celsius.
Adjustments are needed when baking, canning, pressure cooking, and candy making at high altitudes. Consult online resources to adjust recipes.
The Metric Kitchen
Do you need to convert the measurement units used in a recipe? The Metric Kitchen provides easy instructions on how to convert recipes done in teaspoon, cups, and pounds and their metric unit counterparts. A Conversion Style Guide is also available to further explain how metric measurement is used in the art of cooking.