Kilometers to Chains (km to ch)

1 kilometer equals 49.70969538 chains (rounded).

1 kilometer = 49.70969538 chains

How to convert kilometers to chains

To convert kilometers to chains, multiply the number of kilometers by 49.70969538. The factor is rounded to 10 significant digits. To go the other way, multiply chains by 0.0201168.

chains = kilometers × 49.70969538

Example: 10 kilometers = 497.0969538 chains.

About these units

Kilometer (km)

Metric (SI)Current unit

1,000 meters. The standard unit for road distances in most countries.

A name for 1,000 meters took a while to settle. In 1793 France's National Convention made the metre the sole French unit of length, and the first proposed name for the thousand-metre multiple was millaire. Everyday French usage then leaned on the myriametre, 10,000 meters, well into the 1800s. The Netherlands adopted the kilometre in 1817, under the local name mijl, and made it the only official unit of that size in 1867. In 1935 the CIPM dropped the myria- prefix, which left the kilometre as the standard unit for road-scale distances.

Kilo- is the SI prefix for a thousand, and the kilometre is now the preferred unit for land distances in most of the world, with the United States, the United Kingdom and Liberia among those that still use the mile. One kilometre is about 0.621 mile. The main span of Lisbon's 25 de Abril Bridge, at 1.013 km, gives a sense of the scale. Even its pronunciation has been argued over: in 1970 Australia's Metric Conversion Board made stress on the first syllable official, although Prime Minister Gough Whitlam argued for stress on the second. Military slang in several countries calls it a klick.

1 kilometer = 1,000 meters (exactly).

Sources: Wikipedia: Kilometre; Wikipedia: Metric prefix; BIPM: history of the metre

Chain (ch)

US & ImperialTraditional unit (still used in some regions)

22 yards or 66 feet (20.1168 m), also called Gunter's chain. A surveying unit; a cricket pitch is one chain long.

Edmund Gunter, an English mathematician, devised a surveying method in 1620 around a measuring chain of 100 links. Its length of 66 feet was chosen because ten square chains make exactly one acre, so land area could be worked out with simple decimal arithmetic. Surveyors' chains had appeared in Dutch and English sources a few years earlier, but his version gave the chain its standard length and its name. John Ogilby's road atlas Britannia, published in 1675, shows it was widely accepted by then.

The chain equals 22 yards, four rods or exactly 20.1168 m, and 80 chains make a mile. Earlier Scots and Irish chains were longer, at about 74 and 84 feet. American public land surveys from the 1785 Land Ordinance relied on it, and sections are 80 chains on a side. The chain also outlived the surveyor's tool itself: a cricket pitch is one chain between the wickets, British railways still give locations in miles and chains, and fire agencies measure spread in chains per hour.

1 chain = 20.1168 meters (exactly).

Sources: Wikipedia: Chain (unit); NIST SP 811, Appendix B.8 (length conversion factors)

Related conversions

See all length units.