Convert survey miles to kilometers with precision.

If you’ve ever looked at a US land survey or historical map, you’ve probably seen distances measured in survey miles. This isn’t your everyday mile – it’s a slightly different beast rooted in America’s measurement history. Converting survey miles to kilometers isn’t just about multiplying by 1.6; it requires understanding a unique piece of measurement legacy that still impacts property boundaries today.

Why does this matter? Imagine trying to retrace a 19th-century railroad route documented in survey miles. Using standard mile conversions could throw your measurements off by centimeters per mile. Over hundreds of miles, those tiny discrepancies add up to real errors. Our converter handles these nuances so you don’t have to worry about the math.

Unit definitions

What is a survey mile (mi)?

• Description: The US survey mile is a unit of length derived from the now-deprecated US survey foot
• Symbol: mi
• Common uses: Historical land surveys, US Public Land Survey System, older infrastructure plans
• Definition: 5,280 US survey feet, where 1 survey foot = 1200/3937 meters

What is a kilometer (km)?

• Description: The kilometer is the SI unit for length, used globally for most measurements
• Symbol: km
• Common uses: Road signs, athletic events, scientific research
• Definition: 1,000 meters exactly, with 1 meter defined by the distance light travels in 1/299,792,458 seconds

Conversion formula

Survey miles to kilometers:
km = mi × (5,280 × 1200/3937) / 1,000
Simplified:
1 survey mile = 1.609347218 kilometers

Kilometers to survey miles:
mi = km ÷ 1.609347218

Example calculations

1. Converting 5 survey miles to kilometers:
   5 mi × 1.609347218 = 8.04673609 km
2. Converting 10 kilometers to survey miles:
   10 km ÷ 1.609347218 ≈ 6.213727366 mi

Conversion tables

Survey miles to kilometers

Kilometers to survey miles

Historical background

The survey mile’s story begins with the 1893 Mendenhall Order, which defined teh US foot as 1200/3937 meters – a fraction chosen to maintain compatibility with older measurement standards. This created two “feet” in America: the survey foot for mapping and the international foot for trade. In 1959, most countries standardized the foot as 0.3048 meters, but the US kept the survey foot for land measurements to avoid disrupting existing property records.

Fast forward to 2023: The National Institute of Standards finally retired the survey foot, stating all US measurements must use the international foot. However, this change grandfathered existing survey data – meaning any land surveyed before 2023 still legally uses survey miles. It’s a classic case of “if it ain’t broke, don’t fix it,” preserving decades of infrastructure work..

Interesting facts

1. A mile by any other name: The difference between survey and international miles is just 3.2 millimeters per mile – about the width of a grain of rice.
2. Founding fathers’ footprint: The original US survey foot was based on English measures from 1588, preserved in a brass bar called the “Standard Yard.”
3. Landlocked legacy: Over 75% of US states use the Public Land Survey System based on survey miles.
4. Metric resistance: The US is the only industrialized nation still using survey miles in official capacities.
5. Global oddity: Some Canadian border regions use survey miles due to shared historical surveys with the US.

FAQ