Roods to Square Kilometers (rood to km²)

1 rood equals 0.001011714106 square kilometers (rounded).

1 rood = 0.001011714106 square kilometers

How to convert roods to square kilometers

To convert roods to square kilometers, multiply the number of roods by 0.001011714106. The factor is rounded to 10 significant digits. To go the other way, multiply square kilometers by 988.4215259 (rounded).

square kilometers = roods × 0.001011714106

Example: 10 roods = 0.01011714106 square kilometers.

About these units

Rood (rood)

Medieval EnglishHistorical unit (no longer in standard use)

A quarter of an acre (1,011.7 m²), 40 square rods. A medieval English land unit, the area of a furlong by a rod.

Old English rod meant a pole, and especially a cross, which is also why the word names the crucifix screens in medieval churches. As a land measure, the rood was the area of a strip one furlong long and one rod wide, which is the same as 40 square rods. That makes it a quarter of an acre, or 10,890 square feet, about 1,011.7 square meters. Its handiness for surveyors came from the simple fractions: four roods to an acre.

The medieval acre was imagined as a strip a furlong long and four rods wide, the ground a team of oxen could plough in a day, so the rood was the strip left when that width was cut into four. Records in England long gave land as acres, roods and perches, in that order. A separate and obsolete use of rood was as a length, with local values somewhere between about 16.5 and 24 feet. By the time the Oxford English Dictionary was compiled in 1914 that sense survived only locally. Normandy had a comparable unit called the vergee.

1 rood = 1,011.714106 square meters (approximately).

Sources: Wikipedia: Rood (unit); Wikipedia: Acre; Wikipedia: Rod (unit)

Square Kilometer (km²)

Metric (SI)Current unit

One million square meters (100 hectares). Used for the area of cities, countries and lakes.

Metric land measure took a surprisingly long time to settle on the kilometer. The meter was defined in 1799, yet people initially preferred the myriameter, 10,000 meters, and the French phrase myriamètres par heure was still in print in 1802. The Netherlands adopted the kilometer in 1817 under the name mijl. Once the kilometer was established, the square kilometer followed naturally as the unit for areas too large to count comfortably in hectares or square meters.

One square kilometer is 1,000,000 square meters, or 100 hectares, about 0.3861 square miles or 247.1 acres. A useful picture comes from history: many medieval European cities were enclosed by walls around roughly a square kilometer, with Delft at about 0.9 km² and Lucca at about 1.09 km². A standard 18-hole golf course of 6,000 meters needs about 0.8 km². The symbol km² means the square of a kilometer, not a thousand square meters. The planned Square Kilometre Array radio telescope takes its name from the collecting area it aims for.

1 square kilometer = 1,000,000 square meters (exactly).

Sources: Wikipedia: Square kilometre; Wikipedia: Kilometres per hour

Related conversions

See all area units.