Roods to Square Inches (rood to in²)

1 rood equals 1,568,160 square inches exactly.

1 rood = 1,568,160 square inches

How to convert roods to square inches

To convert roods to square inches, multiply the number of roods by 1,568,160. This factor is exact. To go the other way, multiply square inches by 6.376900316×10⁻⁷ (rounded).

square inches = roods × 1,568,160

Example: 10 roods = 15,681,600 square inches.

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 Inch (in²)

US & ImperialCurrent unit

A square one inch on a side, exactly 6.4516 cm². Used for small parts and for pressure (pounds per square inch).

Latin uncia, one twelfth, gave English the inch, which Old English borrowed as ynce. A statute of Edward II in 1324 defined it as three barleycorns, dry and round, set end to end, and the barleycorn remained the base for centuries after 1066. The modern square inch rests on a 20th-century agreement: the United States adopted a yard of exactly 0.9144 meter on 1 July 1959, the United Kingdom followed effective 1 January 1964, and the inch became exactly 25.4 mm.

Squaring that gives exactly 6.4516 cm² for one square inch, and one square meter is about 1,550 of them. Its best-known descendant is the pound per square inch, psi, the pressure unit still used for American tires and air tanks: atmospheric pressure at sea level is about 14.7 psi, a car tire is typically inflated to around 32 psi above the surrounding air, and one psi is about 6.895 kilopascals. The square inch itself is common in the US and UK for small parts and printed material.

1 square inch = 0.00064516 square meters (exactly).

Sources: Wikipedia: Square inch; Wikipedia: Inch; Wikipedia: Pounds per square inch

Related conversions

See all area units.