Choose a Measurement
Select a measurement and convert between different units
Single conversion
To convert from US Survey Foot (ft-us) to Millimeter (mm), use the following formula:
With is the ratio between the base units Meter (m) and Foot (ft).
Let's convert 5 US Survey Foot (ft-us) to Millimeter (mm).
Using the formula:
Therefore, 5 US Survey Foot (ft-us) is equal to Millimeter (mm).
Here are some quick reference conversions from US Survey Foot (ft-us) to Millimeter (mm):
| US Survey Feet | Millimeters |
|---|---|
| 0.000001 ft-us | mm |
| 0.001 ft-us | mm |
| 0.1 ft-us | mm |
| 1 ft-us | mm |
| 2 ft-us | mm |
| 3 ft-us | mm |
| 4 ft-us | mm |
| 5 ft-us | mm |
| 6 ft-us | mm |
| 7 ft-us | mm |
| 8 ft-us | mm |
| 9 ft-us | mm |
| 10 ft-us | mm |
| 20 ft-us | mm |
| 30 ft-us | mm |
| 40 ft-us | mm |
| 50 ft-us | mm |
| 100 ft-us | mm |
| 1000 ft-us | mm |
| 10000 ft-us | mm |
For all Length converters, choose units using the From/To dropdowns above.
The US Survey Foot is a unit of length historically used for land surveying in the United States.
It is very close in length to the international foot, equaling approximately 1.000002 international feet (ft). The plural form is US Survey Feet.
The origin of the US Survey Foot dates back to the Mendenhall Order of 1893. This order defined the relationship between the meter and US customary units.
It established that 1 meter is precisely equal to 39.37 inches. From this relationship, the US Survey Foot was derived, defined as 1200/3937 meters.
This definition differs slightly from the international foot, which was established in 1959 and is defined as exactly 0.3048 meters.
To simplify measurements and prevent confusion, the National Institute of Standards and Technology (NIST) and the National Geodetic Survey (NGS) made a critical change.
They officially retired the U.S. Survey Foot on December 31, 2022.
Surveying and mapping applications in the United States will now use the international foot. This critical change helps unify the National Spatial Reference System (NSRS) and prevents costly errors in large-scale projects.
While the difference between a US Survey Foot and an international foot is minuscule—only about two parts per million—it becomes significant over large distances.
For every mile, the discrepancy adds up to approximately 1/8 inch.
This minor error may not be significant for a backyard fence. However, for massive construction projects and infrastructure development, such as bridges that cross state lines, the accumulated error can lead to severe misalignments and costly mistakes.
A millimeter (mm) is a small unit of length in the metric system, equal to one-thousandth of a meter (1/1000 m or 0.001 m).
The word itself comes from the Latin "mille," meaning "thousand."
This is why the prefix "milli" in the metric system always means one-thousandth of a base unit—just like a milligram is one-thousandth of a gram.
The plural form is millimeters.
Understanding the relationship between millimeters and inches is crucial, particularly for projects that utilize both metric and imperial systems.
The official mm-to-inch conversion is a precise measurement used worldwide in engineering and manufacturing.
The millimeter is the standard unit for measuring small distances with precision.
You likely encounter millimeter measurements more often than you think in daily life, science, and technology.