Skip to main content
Base data: area.
1 tan = 300 bu = 10 une = 0.1 cho ≒ 991.736㎡
Established as 360 bu for one tan under the Taiho Code
1 tan was determined as 360 bu as the area which can produce enough rice to feed 1 person in 1 year under the Taiho Code. It was calculated by multiplying 1 bu (see page 112) by 360 days in 1 year of the old calendar. Then, it was revised to 300 bu in line with agricultural technological progress due to Toyotomi Hideyoshi's nationwide land survey (1582 CE).
©KASAKURA PUBLISHING Co.ltd 2015