What exactly is meant with Feet?

One foot or several feet is a unit of length that primarily appears in English-speaking countries like the United States, Great Britain, or Canada. Through international standardization, one foot is equivalent to exactly 304.8 millimeters or 30.48 centimeters. The official standard symbol for foot is the letters ft, though in daily routine it's often shortened to a single apostrophe like '.

Used by the United States and other major countries, feet are also commonly referenced in countries across Europe, although it's not their official unit of length. A very prominent example is the height of a person. Also in many other parts of industry, construction, aviation, and sports, this unit is used constantly.

How do I convert from Foot to Centimeter?

Both units of length are part of an international system of units and therefore standardized. This is why we can say that the relation between foot and centimeter is always the same. In the year 1959, one foot was fixed to exactly 0.3048 meter. That means one foot can always be equated with 30.48 centimeters.

To convert from feet to centimeters, you multiply the value by 30.48, and the result is the same length in centimeters. To convert from centimeters to feet, you divide the value in centimeters by 30.48. The result is the same length in feet. For example, we can say that 5 feet equals 152.4 centimeters, and in reverse, 150 centimeters equals exactly 4.921259842519685 feet.

Is the unit foot really always the same?

If you look at other countries where the unit of foot isn't the standard, foot is often translated to various other names. This is why people are often unsure whether they can calculate with the standard "foot" or if they have to use another metric. In this case, it's very important to make sure that all parties refer to the international standard "foot" and nothing else.

Solely in older ages (like in the 18th century), different values for feet were used depending on the country or region—such as the Paris foot, the Rhineland foot, or the Viennese foot. But nowadays, as long as foot or feet are used, thanks to standardization, this unit of length is always exactly the same. So if you're unsure whether it has the length you would imagine, you should ask about the length in feet.

What is defined as centimeter?

Centimeter is a unit of length that is normed in the international system of units (SI). It is rooted in other metric systems. The basic unit of centimeter is always the so-called meter (1 meter is 100 centimeters). The international system of units has established itself as the leading system worldwide, and its use is required by law in many countries across the globe.

Although there was historical evolution of the meter over the years, ultimately in 1983 it was mandatorily defined that one meter is equivalent to the distance that light needs in a vacuum during the duration of 1/299,792,458 seconds. Therefore, the number 299,792,458 is the officially normed speed of light in meters per second. That means light needs exactly 3.33564095198152 × 10⁻¹¹ seconds for one centimeter.

Conversion from Foot in other units

There are now just two systems of units relevant: the Anglo-American system and the international system of units. The Anglo-American system remains relevant because countries like the United States, Canada, and Great Britain still use it. In this system, there are numerous units of length beside the foot, such as the inch (abbreviated in), yard (yd), and mile (mi).

One foot is the same as 12 inches, 1/3 of a yard, and 1/5,280 of a mile. Compared to the international system of units, one foot correlates to:

• 304.8 mm (millimeters)
• 30.48 cm (centimeters)
• 3.048 dm (decimeters)
• 0.3048 m (meters)
• 0.0003048 km (kilometers)

Where is the unit Foot also used?

The international system of units is also called the metric system, using the "meter" as its base unit. Over the past few centuries, it has become the most commonly used system worldwide. However, the United States, Liberia, and Myanmar haven't made it mandatory.

Furthermore, countries like Great Britain have accepted the metric system in daily use but haven't officially introduced it entirely. This is why the Anglo-American system is and will remain common in the United States, Canada, Great Britain, Australia, New Zealand, India, Ireland, and Malaysia—with foot being a very familiar unit for measuring height, room dimensions, and altitude.

In aviation, altitude is universally measured in feet worldwide, regardless of the country's measurement system. This standardization is critical for flight safety and international air traffic control.

Meaning and origin of the term Foot

The term "foot" originates from the Latin pes (plural: pedes), which also meant "foot" both as a body part and a unit of measurement. This ancient unit was based on the length of an adult human foot. Through language evolution over the centuries, the Latin "pes" transformed into the English "foot."

Beyond using foot or feet as a unit of length, there are numerous phrases and expressions in English:

• "To put your best foot forward" - to make a good impression
• "To stand on your own two feet" - to be independent
• "To foot the bill" - to pay for something
• "Cold feet" - to lose courage at the last moment
• "To shoot yourself in the foot" - to harm your own interests

Terms survey foot/square foot/cubic foot

In English-speaking countries, terms like survey foot, square foot, and cubic foot are very common and frequently used, each with a different meaning:

Survey Foot

The survey foot has historic roots in the United States and is still used there for precise land surveying. In 1866, it was defined as exactly 0.30480061 meters by the U.S. government. Since then, it coexists with the more common international foot (exactly 0.3048 meters). The difference is only 0.000061 cm, which is negligible for most purposes but matters for precise land surveying.

Square Foot

The square foot is a unit of area, not length. It's the area measure specified in feet (ft²). Square feet are the common way in the United States to declare the area of real estate, apartments, or houses. One square foot equals exactly 0.09290304 square meters.

Cubic Foot

The cubic foot is a unit of volume based on dimensions in feet (ft³). One cube with an edge length of one foot has a volume of exactly one cubic foot, which equals approximately 28.3168 liters. This measurement is commonly used for shipping, storage, and appliance capacity.

Which products are specified in Foot/Feet?

Many major industries, especially aviation and construction, are dominated by companies from the United States. As a result, specifications for height, altitude, and dimensions are often given in feet:

• Aircraft altitude is universally measured in feet worldwide
• Lumber dimensions and building materials
• Room sizes and ceiling heights in construction
• Human height measurement in many countries
• Shipping containers (20-foot, 40-foot containers)
• Sports fields, particularly in American football
• Boat and yacht lengths

All these length measurements can be converted to centimeters anytime using our calculator above.

History of the Foot

The first standardized units called "foot" date back to ancient civilizations. The Egyptians used a royal foot of about 30 cm, while the Romans established the "pes" at approximately 29.6 cm, divided into 12 unciae (inches). These Roman measurements spread throughout their empire.

In Great Britain, the foot became a standard unit after the Roman occupation, but local variations persisted for centuries. In 1324, King Edward II of England defined one inch as three barley corns, which indirectly defined the foot as 36 barley corns. The critical turning point came in 1959 when the United States, United Kingdom, and other Commonwealth countries agreed to define the international foot as exactly 0.3048 meters, aligning it with the metric system and ending centuries of regional variations.

Quotes with Foot/Feet