By Phuket News Property · November 11, 2021
Understanding how land is measured in Thailand is essential for anyone considering a property purchase. Thailand uses a traditional system of measurement that differs from Western units, and knowing how these measurements convert can help buyers read title deeds, review plans and compare land plots with confidence.
The traditional Thai land measurement system
Land in Thailand is measured using three main units: Wah, Ngan and Rai. These units appear on title deeds, survey documents and land-office records throughout the country.
What each unit represents
Wah (or Square Wah)
The smallest common unit.
One Square Wah equals four square metres.
Ngan
Used for medium-sized plots.
One Ngan equals 100 Square Wah.
Rai
The standard unit for larger plots.
One Rai equals four Ngan, or 400 Square Wah.
Converting Thai land units into square metres
Foreign buyers often compare land size using square metres. Conversions are straightforward:
• 1 Square Wah = 4 sqm
• 1 Ngan = 100 Square Wah = 400 sqm
• 1 Rai = 4 Ngan = 400 Square Wah = 1,600 sqm
These conversions help when comparing Thai plots with international property listings or calculating approximate development areas.
Why these units matter for buyers
Land size descriptions in Thailand typically use Rai, Ngan and Square Wah regardless of whether the land is for residential building, commercial development or agricultural use. Buyers should understand these units to interpret title deeds accurately and to confirm boundaries during surveys or inspections.
Confirming measurements before buying land
Before purchasing any land, ensure that the measurements listed on the title deed match physical boundaries. Licensed surveyors and legal professionals can help verify the size, confirm access, and check for discrepancies that may affect development or future resale.
