Area Converter / Tool

Converts the entered unit of area to another unit.(m2, sq.in., Japanese units, ha, etc.)

• Rounded to the fourteenth decimal place.

Metric system

 square millimeter mm2 square centimeter cm2 square meter m2 are a hectare ha square kilometre km2

United States customary units / Imperial units

 square inch sq.in. square foot sq.ft. square yard sq.yd. rood ro acre ac square mile sq.mi.

Japanese units of measurement

 shaku 勺 gō 合 tsubo 坪 se 畝 tan 反 chō 町 jō 畳／帖
A number with many digits may appear as "1e9". This is the computer's exponential representation, where "e" is a power of 10.
1e3 = 103 = 1,000
1e6 = 106 = 1,000,000
1e9 = 109 = 1,000,000,000
1e-3 = 10-3 = 0.001
1e-6 = 10-6 = 0.000001
1e-9 = 10-9 = 0.000000001

Area conversion formula

Metric system

$1 km^2 = 10^2 ha = 10^4 a = 10^6 m^2$
$1 m^2 = 10^4 cm^2 = 10^6 mm^2$

United States customary units / Imperial units

$1 sq \ mi = 640 ac$
$1 ac = 4 ro = 4840 sq \ yd$
$1 sq \ yd = 9 sq \ ft$
$1 sq \ ft = 144 sq \ in = 929.0304 cm^2$
$1 sq \ in = 645.16 mm^2$

Japanese units of measurement

$1\text{町} = 10\text{反} = 100\text{畝} = 3000\text{坪}$
$1\text{坪} = {\dfrac {400}{121}} m^2 \approx 3.305785 m^2$
$1\text{坪} = 10\text{合} = 100\text{勺}$
$1\text{畳／帖} = 1.62 m^2 \ (*)$

*** About tatami mats (畳 / 帖 / jō)**
When written as “畳”, it is not always 1.62 m2. There are various dimensions of tatami mats such as Edo-ma and Kyo-ma. I made ”Unit Converter: Tatami”, so please use it.

When written as “帖”, it is 1.62 m2. The “畳 / 帖” written in the recent housing advertisement is 1.62 m2.

Hirota Yano / Born in 1987. Programmer.
I am publishing a web tool I created as a hobby. It is free of charge, so please feel free to use it.