Se to Acres (se to ac)

1 se equals 0.02450631882 acres (rounded).

1 se = 0.02450631882 acres

How to convert se to acres

To convert se to acres, multiply the number of se by 0.02450631882. The factor is rounded to 10 significant digits. To go the other way, multiply acres by 40.80580226 (rounded).

acres = se × 0.02450631882

Example: 10 se = 0.2450631882 acres.

About these units

Se (se)

JapaneseTraditional unit (still used in some regions)

30 tsubo, about 99.17 m².

Between the humble tsubo and the field-sized tan sits the se, a plot of 30 tsubo. In square metres that is exactly 12,000/121, or about 99.17, which is just under one are, the metric land unit of 100 square metres. A se measures roughly ten metres by ten, a small garden or a slice of a paddy.

The scale is decimal above this point. Ten se make one tan, and a hundred se make one cho, so the se works as the first step in the farmland ladder rather than a unit with a life of its own. Property listings today seldom use it, and it is mostly met in old land records and in conversion tables.

Its exact size comes from the Meiji legal definition. The 1891 law set the shaku at 10/33 metre, and the tsubo as the square of six shaku, so every larger land unit built on the tsubo inherited a fixed metric value. Before that, the shaku itself varied by era and use.

1 se = 99.17355372 square meters (approximately).

Sources: Wikipedia: Japanese units of measurement; Wikipedia: Shaku (unit); Wikipedia: Tsubo

Acre (ac)

US & ImperialCurrent unit

43,560 square feet or exactly 4,046.8564224 m², about 40% of a hectare. Originally the area a yoke of oxen could plow in a day.

Ploughland gave the acre its name: it traces to Old Norse akr, meaning cultivated land, and is related to German Acker and Latin ager. In medieval England it was a farming measure, the land one man with a team of eight oxen could plough in a day. The traditional strip was 40 perches long and 4 perches wide, which is 660 by 66 feet, or ten square chains. The shape was never the point, and the article on the unit stresses that any area of 43,560 square feet is an acre.

An acre is 43,560 square feet, 4,840 square yards or 1/640 of a square mile, close to 0.4 hectare. For Americans, it is roughly 88 by 55 yards, about 90 percent of a football field without the end zones. The Weights and Measures Act 1878 fixed it at 4,840 square yards in Britain, where trade use ended in 1995. The 1959 international acre is exactly 4,046.8564224 m²; the US survey acre, about 4,046.872 m², differed slightly, and US survey units were retired after 2022.

1 acre = 4,046.856422 square meters (approximately).

Sources: Wikipedia: Acre; NIST Guide to the SI, Appendix B.8: conversion factors

Related conversions

See all area units.