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Single conversion
To convert from Mil (mil) to US Survey Foot (ft-us), use the following formula:
Let's convert 5 Mil (mil) to US Survey Foot (ft-us).
Using the formula:
Therefore, 5 Mil (mil) is equal to US Survey Foot (ft-us).
Here are some quick reference conversions from Mil (mil) to US Survey Foot (ft-us):
| Mils | US Survey Feet |
|---|---|
| 0.000001 mil | ft-us |
| 0.001 mil | ft-us |
| 0.1 mil | ft-us |
| 1 mil | ft-us |
| 2 mil | ft-us |
| 3 mil | ft-us |
| 4 mil | ft-us |
| 5 mil | ft-us |
| 6 mil | ft-us |
| 7 mil | ft-us |
| 8 mil | ft-us |
| 9 mil | ft-us |
| 10 mil | ft-us |
| 20 mil | ft-us |
| 30 mil | ft-us |
| 40 mil | ft-us |
| 50 mil | ft-us |
| 100 mil | ft-us |
| 1000 mil | ft-us |
| 10000 mil | ft-us |
For all Length converters, choose units using the From/To dropdowns above.
A mil is a tiny unit of length in the imperial system of measurement.
Its most crucial definition is simple: one mil is equal to one-thousandth of an inch (1/1000 or 0.001 inches).
The plural form of the unit is mils.
The name "mil" comes from the Latin word millesimum, which means "thousandth"—a perfect fit for a unit that represents 1/1000th of an inch.
In engineering and manufacturing, especially in the UK, you might also hear a mil referred to as a thou. This nickname helps prevent confusion with metric units, such as the millimeter.
The mil measurement is essential in industries where precision is key, even over minimal distances.
To give you some perspective, a human hair is about 2 to 4 mils thick.
This unit is commonly used to specify the thickness or diameter of:
It's crucial not to confuse the imperial mil with the metric millimeter (mm). A millimeter is a much larger unit of measurement.
Here's a simple breakdown of the mil vs. mm conversion:
As you can see, one millimeter is nearly 40 times larger than one mil.
It is crucial to specify the units used in technical specifications to avoid significant mistakes.
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.