tsubo
tsubo
Areaexact by definition
The tsubo is exactly 400/121 square metres, about 3.306 m², the area of two standard tatami mats. Japanese real estate is advertised and priced per tsubo, and floor areas of houses and apartments are quoted in them alongside the metric figure.
Watch out: The Korean pyeong is the same size, exactly 400/121 m², and was officially abolished for commercial use in 2007 but is still spoken. Taiwan's ping is the same unit again. All three are the same area under three names.
| 1 tsubo | 3.3057851 m² |
Where the unit came from
It derives from the ken, a traditional module of Japanese carpentry: one tsubo is one square ken. Because the whole building system was laid out on that grid, room sizes fall naturally on whole tsubo, which is why the unit outlived metrication.
Solvers that use area