Convert Length from Inch to Foot (in to ft)

Inch to Foot Conversion Formula

To convert from Inch (in) to Foot (ft), use the following formula:

Example

Let's convert 5 Inch (in) to Foot (ft).

Using the formula:

Therefore, 5 Inch (in) is equal to $0.41666666666666666667$ Foot (ft).

What is an Inch?

An inch (in) is a standard unit of length used in the imperial and United States customary systems.

It is most commonly known as 1/12 of a foot. The plural form is "inches."

For a quick inch definition, here are the most important conversions:

• 1 inch = 1/12 of a foot
• 1 inch = 2.54 centimeters (exactly)
• Symbol: in or "

Where Did the Inch Come From?

The history of the inch goes back centuries. The word "inch" itself originates from the Latin word uncia, meaning "one-twelfth," which highlights its relationship to the larger unit of a foot.

Early definitions were often based on natural reference points. For a long time, an inch was widely considered to be the width of a man's thumb at the base of the nail.

To create a more reliable standard, 14th-century English King Edward II officially defined the inch as the length of three grains of barley placed end to end.

How is an Inch Defined Today?

While the inch is an imperial unit, its official modern definition is based on the metric system.

Since 1959, an international agreement has defined the inch as exactly 2.54 centimeters (or 25.4 millimeters).

This universal standard, agreed upon by the United States, the United Kingdom, and other nations, ensures that the inch has a precise and globally recognized value.

This consistency is crucial for international trade, engineering, and science.

How Are Inches Used for High-Precision Measurements?

In fields that require extreme accuracy, such as engineering and machining, the inch is often divided into even smaller parts.

One-thousandth of an inch (1/1000 or 0.001 inches) is commonly known as a "thou" or a "mil."

Although very small, this unit is crucial for defining tolerances in the manufacture of engine components, electronic devices, and other precision equipment, where minute differences can have significant effects.

By comparison, a standard piece of paper measures roughly 2–4 thou in thickness.

What is a Foot (ft)?

The foot (ft) is a standard unit of length in the Imperial and U.S. customary systems of measurement.

The plural form is feet.

How Many Inches Make a Foot?

There are exactly 12 inches in a foot.

This fundamental conversion is the cornerstone of the Imperial and U.S. customary systems. It's a standard used everywhere, from measuring personal height to completing construction projects.

Additionally, it's helpful to know that 3 feet make one yard.

The History of the Foot Measurement

The origin of the "foot" as a unit of measurement is quite literal—it was historically based on the average length of a human foot.

Ancient civilizations, such as the Greeks, Romans, and Egyptians, often used body parts as a basis for measurement.

Because the actual length of a person's foot could vary, so did the measurement. This led to many inconsistencies until the foot was officially standardized.

How Is the Foot Used Today?

Although most of the world uses the metric system, the foot is still an official unit of length in the United States.

It is also commonly used in countries such as the United Kingdom and Canada, particularly for measuring height, altitude, and property dimensions.

To establish a global standard, the international foot was defined in 1959 as being exactly 0.3048 meters.

This precise conversion is crucial for international science, trade, and engineering.

What is the imperial system?

Inch to Foot Conversion Table

Here are some quick reference conversions from Inch (in) to Foot (ft):