Rai – the Thai measuring unit explained

On this website you have probably noticed our use of the measuring unit Rai (ไร่). Although the metric system is the official measuring system used in Thailand, some traditional measuring units, like the rai, are still in use. In Thai, the rai, abbreviated to ‘r’, also means plantation. It equals exactly 1600 square meters. When buying and selling land, the number of rai is what the Thai want to know.

Two other traditional measuring units are the Ngaan (งาน) and the Tarangwa (ตารางวา). 1 ngaan equals 400 square meters; 1 tarangwa equals 4 square meters. To make it a little bit clearer, I have created this table:

1 square meter = 1 m2 1/1600 rai 1/400 ngaan 1/4 tarangwa
1 rai = 1600 m2 1 rai 4 ngaan 400 tarangwa
1 ngaan = 400 m2 1/4 rai 1 ngaan 100 tarangwa
1 tarangwa = 4 m2 1/400 rai 1/100 ngaan 1 tarangwa