Understanding Thailand's Land Measurement System: Rai, Ngan, and Wah Explained

By Peer Johannsen, Managing Director, Pearl Property Pattaya • Last updated: May 22, 2026

When looking to invest in real estate in Pattaya or other parts of Thailand, it's essential to understand the country's unique land measurement system. We will explain the units of measurement, their divisible relationship to each other, and how they compare to other international systems so you can get a sense of perspective and the size of each unit.

Thailand's Land Measurement System

Rai

The rai is the largest unit of land measurement in Thailand. It is commonly used for larger land areas, such as agricultural land, houses, and villas. One rai is equivalent to 1,600 square meters or approximately 0.40 acres.

Ngan

The ngan is a smaller unit of measurement, commonly used for medium-sized land plots. One ngan is equivalent to 400 square meters or 0.10 acres. There are four ngan in one rai.

Wah

The wah is the smallest unit of land measurement in Thailand. It’s used for measuring small land areas or accurately describing smaller areas within a larger plot of land. One wah is equivalent to 4 square meters or 0.001 acres. There are 100 wah in one Ngan and 400 wahs in one rai.

Converting Thai Land Measurements to International Units

To better understand the size of a property in Thailand, it may be helpful to convert the local measurements to more familiar units like square meters, square feet, or acres. Here are some conversion factors to help you:

• 1 rai = 1,600 square meters
• 1 rai = 17,222 square feet
• 1 ngan = 400 square meters
• 1 ngan = 4,305 square feet
• 1 wah = 4 square meters
• 1 wah = 43 square feet

Using Thai Land Measurements in Property Listings

When browsing Pattaya property listings, you'll find land measurements in rai, ngan, or wah. It's essential to be familiar with these units to accurately assess the property size for a more familiar perspective and compare it to other properties in the market. For example, if a condo development is listed as having a land size of 2 rai, 1 ngan, and 50 wah, you can convert this to square meters using the conversion factors mentioned above:

• 2 rai = 3,200 square meters
• 1 ngan = 400 square meters
• 50 wah = 200 square meters

Added together, the total land size is 3,800 square meters.

Practical Applications of Thai Land Measurements

Frequently Asked Questions