Convert Tsubo to Square Millimeters

Convert Tsubo (坪) to Square Millimeters (mm²) instantly and accurately.

Tsubo (坪)
Square Millimeters (mm²)

Conversion Formula

mm² = 坪 × 3305785.124

About Tsubo

A tsubo (坪) is the traditional Japanese unit of floor area, equal to 400/121 m² (approximately 3.306 m²) - defined as the footprint of two tatami mats placed side by side. It has been the standard for measuring rooms and apartments in Japan for centuries and remains widely used in real estate and architecture today. Apartment sizes in Japan are routinely quoted in tsubo alongside square meters. One tsubo equals approximately 35.58 square feet or 3.95 square yards.

About Square Millimeters

A square millimeter (mm²) is a metric unit of area equal to a square with sides of one millimeter. It is commonly used in precision engineering, electronics, and measuring very small surfaces such as microchips or printed circuit boards. To visualise: a typical pinhead has an area of about 2-3 mm². This unit is essential in microscopy, medical imaging, and manufacturing where tiny, precise measurements are critical.

Quick Reference Table

Tsubo (坪)Square Millimeters (mm²)
1 坪3305790 mm²
2 坪6611570 mm²
5 坪16528900 mm²
10 坪33057900 mm²
25 坪82644600 mm²
50 坪165289000 mm²
100 坪330579000 mm²

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