# Standard units of measurement

All Fillet apps use the same standard units of measurement.

Learn about standard units and how to use them in Fillet apps.

## Standard units

Standard units are units of measurement that provide consistent or uniform measurement. You cannot create or add standard units in Fillet. To use non-standard units, you must create abstract units.

There are three major systems for standard measurement:

• the British Imperial System
• the U.S. Customary System
• SI, the International System of Units.

(SI is the modern form of the metric system. In everyday usage, it is still commonly referred to as the metric system.)

##### Important

Fillet uses only SI (metric) units and U.S. Customary System units.

In Fillet apps, when you see units of measurement such as “cup”, “pt”, or “lb”, this refers to the U.S. Customary System.

## Units of measurement for mass and volume

The most commonly used standard units are mass and volume units.

• Mass is the heaviness or weight of something.

• Some examples of mass units are kilograms ("kg"), grams ("g"), pounds ("lb"), and ounces ("oz").

• Volume is the amount of space that something occupies.

• Some examples of volume units are liters ("L"), milliliters ("mL"), gallons ("gal"), pints ("pt"), tablespoons ("tbsp"), and teaspoons ("tsp").

Volume is often used to measure liquids, but you can use volume to measure substances in different forms.

For example, "1 tablespoon of sugar", "1 cup of chopped carrots", "1 gallon of ice cream".

Tip: Measuring amounts using mass is generally more precise than using volume. If volume measurements are more convenient, you should specify conversion from volume to mass.

## Standard units in Fillet

All Fillet apps use the same standard units of measurement.

There are two categories of standard units: mass units and volume units. Fillet apps only use SI (metric) and US customary units for mass and volume.

Since these are all standard units, the measurement values never change.

Note: You cannot create or add standard units in Fillet. To use non-standard units, you must create abstract units.

#### Uses of standard units

In Fillet, you will typically use standard units to do the following: