What Is Mile (US Survey)?
The mile (US survey) is a unit used mainly in American land surveying. It measures long distances on maps, property lines, and large land areas. It is almost the same as the regular mile used for driving, but it is very slightly longer. Today it survives mostly in old maps, legal land documents, and some survey work.
Definition
A mile (US survey) is defined by the survey foot, not by the meter directly.
The exact definition is:
- 1 mile (US survey) = 5,280 survey feet
- 1 survey foot = exactly 1200 / 3937 meters
Using this, we get:
- 1 mile (US survey) ≈ 1,609.347218694 meters
- 1 mile (US survey) ≈ 1.609347 kilometers
This makes the US survey mile only a tiny bit longer than the international mile used in most places, which is exactly 1,609.344 meters.
History / Origin
The idea of a mile comes from ancient Rome, where a mile was 1,000 double steps taken by a soldier. Over time, many countries created their own versions of the mile.
In the United States, the mile became fixed as 5,280 feet. In 1893, the US government tied survey measurements to the meter using a special rule. This created the survey foot, and from that, the mile (US survey) was set as 5,280 survey feet.
In 1959, the United States and several other countries agreed on a new standard for the yard and foot, which created the international foot and the international mile. The new international mile is almost the same as the old survey mile, but not perfectly.
Changing every map and land record to the new mile would have been very hard and costly. So the US kept the survey mile and survey foot for land surveying and mapping, especially for older systems like the Public Land Survey System.
In recent years, the United States has moved toward using the international foot and metric units for most work, but old data and some laws still refer to the US survey mile.
Symbol & Abbreviation
The common symbol for a mile (US survey) is:
- mi
However, the normal road mile (international mile) also uses mi, so people sometimes add extra words to show that it is the survey mile. You may see:
- mi (US survey)
- US survey mi
- US surv mi
- spelled out as mile (US survey)
These longer forms help avoid confusion in technical work, maps, and legal papers.
Current Use Around the World
The mile (US survey) is a very specialized unit today. It is not used on road signs or in everyday life.
United States:
- Used in some land surveying and mapping, especially with older data sets
- Appears in property deeds, land titles, and other legal land descriptions
- Found in some government maps and geographic information systems (GIS) that were built before newer rules
Other countries:
- Almost never used outside the United States
- Most countries use meters and kilometers for surveying and mapping
Modern survey work in the US is slowly moving more toward the meter and the international foot, but the US survey mile will remain in old records for a long time.
Example Conversions
Here are some simple conversion examples. Values are rounded for easy reading.
From mile (US survey) to metric
- 1 mile (US survey) ≈ 1,609.347 meters
- 1 mile (US survey) ≈ 1.6093 kilometers
- 5 miles (US survey) ≈ 8.0467 kilometers
- 10 miles (US survey) ≈ 16.0935 kilometers
From metric to mile (US survey)
- 1 kilometer ≈ 0.62137 mile (US survey)
- 5 kilometers ≈ 3.1069 miles (US survey)
- 10 kilometers ≈ 6.2137 miles (US survey)
To other US survey units
- 1 mile (US survey) = 5,280 survey feet
- 1 mile (US survey) = 1,760 survey yards
- 1 mile (US survey) = 63,360 survey inches
- 1 mile (US survey) = 80 survey chains (1 chain = 66 survey feet)
- 1 mile (US survey) = 8 survey furlongs (1 furlong = 660 survey feet)
Difference from international mile
- 1 mile (international) = exactly 1,609.344 meters
- 1 mile (US survey) ≈ 1,609.3472187 meters
- Difference ≈ 0.0032 meters per mile (about 3.2 millimeters)
This difference is tiny and matters only in high precision surveying or over very long distances.
Related Units
The mile (US survey) is connected to several other length units used in surveying and everyday life:
- Foot (US survey) – the basic unit that defines the survey mile, 1 mile (US survey) = 5,280 survey feet
- Foot (international) – slightly different from the survey foot, used in most modern measurements
- Mile (international) – the standard mile for road distances, sports, and general use, very close to the survey mile but not exactly the same
- Kilometer (km) – main metric unit for long distances, 1 km ≈ 0.62137 mile (US survey)
- Meter (m) – base metric unit of length, used to define both foot types
- Yard – 3 feet, used in some US and UK measurements
- Chain – 66 feet, used in old land surveys, 80 chains = 1 mile (US survey)
- Furlong – 660 feet, used in horse racing and old land measures, 8 furlongs = 1 mile (US survey)
- Nautical mile – used at sea and in aviation, based on the Earths shape, about 1.1508 international miles
FAQs
What is the mile (US survey) in simple words?
It is a special version of the mile used in American land surveying. It is defined using the survey foot and is used for maps and property lines, not for road travel.
How is the mile (US survey) different from a normal mile?
The normal mile, also called the international mile, is exactly 1,609.344 meters. The US survey mile is about 1,609.347 meters. So the survey mile is about 3 millimeters longer. In everyday life this difference does not matter, but in precise mapping it does.
Why was the mile (US survey) created?
It came from older US rules that tied survey measurements to the meter in a certain way. When new world standards for the foot and mile were set in 1959, the United States kept the old survey versions for land records so they would stay consistent.
Is the mile (US survey) still used today?
Yes, but only in limited areas. It is used in some land surveying, old maps, property deeds, and geographic databases in the United States. Most daily measurements use the international mile or metric units instead.
Which symbol should I use for the mile (US survey)?
For simple writing, you can use mi. For technical work, it is better to write mi (US survey) or mile (US survey) so no one confuses it with the international mile.
How can I quickly convert miles (US survey) to kilometers?
A quick rule is: multiply miles (US survey) by about 1.609. For example, 10 miles (US survey) × 1.609 ≈ 16.09 kilometers. For most uses, this is accurate enough.
Do GPS devices use the mile (US survey)?
Most GPS devices and phone maps use international units and metric units, not the US survey mile. The US survey mile mainly appears in background survey data and old mapping systems.