Customary Units of Length

When we measure the length of any object, we have to include the unit of the measurement. By including a unit, we specify on which scale the measurement is being made.

Example
If you measure a shoebox, you can say that it measures 12 units.
Which units? 12 inches? 12 feet? 12 miles? If a shoebox measured 12 miles, you would be able to drive for 20 minutes on it! A shoe box measures 12 inches.

There are two different types of units:

1. Customary Units
2. Metric Units

Customary Units
Customary units are used only in the United States and were born from English units, a system that the British used even before the U.S. gained independence. Customary units of length include units like inch, foot, yard and mile.

Customary Units Conversion Here, you can see the conversion table for all customary units.

Customary units order from smallest to larger goes:

Inch (in)
Foot (ft)
Yard (yd)
Mile (mi)

1 in x 12 = 1 ft
1 ft x 3 = 1 yd
1 yd x 1760 = 1 mi

Example
To measure a fingernail, you can use the smallest customary units like centimeter, or inch – you can estimate that a nail is about 3 cm or 1/2 inch.

Example
To measure a table, you can use larger scale like feet – a dining room table is probably about 6 ft.