Convert Length from Mils to US Survey Feet (mil to ft-us)

Select a category and enter your values below

Single conversion

Mil to US Survey Foot Conversion Formula

To convert from Mil (mil) to US Survey Foot (ft-us), use the following formula:

US Survey Foot (ft-us)

= 112000 × 11.000002× Mil (mil)

= 0.000083333166666999999333× Mil (mil)


Example

Let's convert 5 Mil (mil) to US Survey Foot (ft-us).

Using the formula:

5 × 0.000083333166666999999333 = 0.00041666583333499999667

Therefore, 5 Mil (mil) is equal to 0.00041666583333499999667 US Survey Foot (ft-us).

How many mils are in one us survey foot? One US Survey Foot (ft-us) contains 12000.024 Mils (mil) — the inverse of the factor above. Multiplying by 0.000083333166666999999333 takes you from mils to us survey feet; multiplying by 12000.024 brings you back.

Put in words: one mil equals 0.000083333166666999999333 us survey feet, so the mil is the smaller unit of this pair. Converting between them never changes the amount of length being measured — only the size of the unit you count it in.

What is a Mil?

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.


Where Does the Name 'Mil' Come From?

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.


What is a Mil Used For?

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:

  • Thin materials like plastic bags and foils
  • Coatings, such as layers of paint or plating
  • Paper and cardstock
  • Wires and electrical conductors
  • Manufacturing tolerances for electronic parts, like printed circuit boards (PCBs)

Mil vs. MM: What's the Difference?

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:

  • 1 mil = 0.0254 mm
  • 1 mm = 39.37 mils

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.

What is a US Survey Foot (ft-us)?

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.


Where Did the US Survey Foot Come From?

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.


Why Was the US Survey Foot Replaced?

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.


Why Did This Small Difference Cause Big Problems?

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.

Mil to US Survey Foot Conversion Table

Here are some quick reference conversions from Mil (mil) to US Survey Foot (ft-us):

MilsUS Survey Feet
0.000001 mil8.3333166666999999333× 10-11 ft-us
0.001 mil8.3333166666999999333× 10-8 ft-us
0.1 mil0.0000083333166666999999333 ft-us
1 mil0.000083333166666999999333 ft-us
2 mil0.00016666633333399999867 ft-us
3 mil0.000249999500000999998 ft-us
4 mil0.00033333266666799999733 ft-us
5 mil0.00041666583333499999667 ft-us
6 mil0.000499999000001999996 ft-us
7 mil0.00058333216666899999533 ft-us
8 mil0.00066666533333599999466 ft-us
9 mil0.000749998500002999994 ft-us
10 mil0.00083333166666999999333 ft-us
20 mil0.0016666633333399999867 ft-us
30 mil0.00249999500000999998 ft-us
40 mil0.0033333266666799999733 ft-us
50 mil0.0041666583333499999667 ft-us
100 mil0.0083333166666999999333 ft-us
1000 mil0.083333166666999999333 ft-us
10000 mil0.83333166666999999333 ft-us

List some Length Converters

For all Length converters, choose units using the From/To dropdowns above.