Land Measurements

If you are buying property in Thailand the measurements can become confusing. It is neither imperial nor metric. We have a convertor on our site to convert Rai into square meters. The Thai system has not changed and when buying property it is best to understand it.

The metric system was officially introduced by a law passed on December 17, 1923. However, old Thai units are still in common use, especially for measurements of land which is often quoted using the traditional Thai system of waa, ngaan and rai. Old-timers in the provinces will occasionally use the traditional Thai system of weights and measures in speech, as will boat-builders, carpenters and other craftsmen when talking about their work. Here are some conversions to use for such occasions:

Thai system

Metric System
1 square wha 4 square meters
1 ngan (100 square wha) 400 square meters
1 rai (4 ngan) (1 sq cen) 1600 square meters
1 baht 15.16 grams
1 tamlung (4 Baht) 60 grams
1 chang (20 tamlung) 1.2 kg
1 haap (50 chang) 60 kg
1 niu 2 cm
1 kheup (12 niu) 25 cm
1 sawk (2 kheup) 50 cm
1 waa (4 sawk) 2 meters
1 sen (20 waa) 40 meters
1 yoht (400 sen) 16 km
1 kwien 2,000 liters
1 ban 1,000 liters (2 ban=1 kwien)
1 sat 20 liters (50 sat=1 ban)
1 tannan 1 liter (20 tannan=1 sat)