A surveyor's chain is 66 feet.
Chains to Kilometers Converter — ch to km
Convert Chain (ch) to Kilometer (km) using the exact conversion factor (1 chain = 0.0201168 kilometer). See the formula, worked examples, conversion table, history, and common uses.
Chains to Kilometers converter
Converter
Length Converter
Convert SI, imperial, US customary, astronomical, scientific, and historical length units.
Context values
Some unit families need one extra value for a physically accurate result.
Kilometer is 1000 meter units.
Result = input x 20.1168 / 1000.
Length uses the meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Chains to Kilometers
Chain and Kilometer both measure length. Specifically: A surveyor's chain is 66 feet, and kilometer is 1000 meter units.
Formula
kilometers = chains × 0.0201168
This factor comes from each unit's defined relationship to the category's base unit: 1 chain equals 20.1168 base units, and 1 kilometer equals 1000 base units, so dividing one by the other gives the direct chain-to-kilometer factor of 0.0201168.
Simple example
1 ch × 0.0201168 = 0.0201168 km
1 chain = 0.0201168 kilometers.
Real-world example
10 ch × 0.0201168 = 0.201168 km
10 chains = 0.201168 kilometers.
Conversion table
| Chain (ch) | Kilometer (km) |
|---|---|
| 1 ch | 0.0201168 km |
| 5 ch | 0.100584 km |
| 10 ch | 0.201168 km |
| 21.0975 ch | 0.424414188 km |
| 42.195 ch | 0.848828376 km |
| 100 ch | 2.01168 km |
Reverse conversion: Kilometer to Chain
0.0201168 km × 49.70969538 = 1 ch
0.0201168 kilometers = 1 chain.
chains = kilometers × 49.709695379
For a page dedicated to this direction, see Kilometer to Chain.
Understanding the Chain (ch)
A surveyor's chain is 66 feet.
Understanding the Kilometer
Kilometer (km) measures distance. A kilometer is 1,000 meters — the meter is the SI base unit of length. It is classified as a SI derived (metric prefix) unit.
Where it's used: Standard road, distance, and mapping unit in nearly every country except the United States
Uses of the Kilometer today
- Road signage, speed limits, and vehicle odometers outside the US
- Geographic and mapping distances
- Endurance sports (marathons are measured in kilometers internationally, though the marathon distance itself is a fixed value in both systems)
History of the Kilometer
The meter was defined during the French Revolutionary metric reforms as one ten-millionth of the distance from the North Pole to the Equator along a meridian through Paris. 'Kilo-' is simply the SI prefix for 1,000, making the kilometer a direct decimal multiple.
The meter itself has been redefined several times as measurement precision improved — from a physical platinum-iridium bar (1889) to a krypton-86 wavelength (1960) to its current definition (1983) as the distance light travels in a fixed fraction of a second.
Historical origin. Kilometer was not the invention of a single named person; it developed through the process described above.
Kilometer — sources
- BIPM — The metre (SI base unit) — Current definition and history of the meter.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many kilometers are in 1 chain?
1 chain equals 0.0201168 kilometers, using the exact defined conversion factor rather than an estimate.
How do I convert chain to kilometer?
Multiply the chain value by 0.0201168. The converter above does this instantly to whatever precision you set.
How do I convert kilometer back to chain?
Use the reverse factor: 1 kilometer equals 49.70969538 chains. You can also use the swap control in the converter above to flip the direction instantly.
What is a chain?
Chain (ch) is a unit of length.
What is a kilometer?
Kilometer (km) measures distance. A kilometer is 1,000 meters — the meter is the SI base unit of length. It is classified as a SI derived (metric prefix) unit.
Is the chain to kilometer conversion exact?
Yes. Both chain and kilometer are defined by fixed standards rather than physical artifacts, so the factor of 0.0201168 used above is exact to as many digits as you choose to display.