One rai is exactly 1,600 m². Thailand fixed its land units to the metric system, so the rai is a square 40 m on a side and splits cleanly into 4 ngan of 400 m² and 400 square wah of 4 m². Converting is plain multiplication: 3 rai are 4,800 m² and a quarter rai (one ngan) is 400 m².
Formula
Rai to Square Meters conversion table
| Rai | Square Meters |
|---|---|
| 1 rai | 1,600 m² |
| 2 rai | 3,200 m² |
| 3 rai | 4,800 m² |
| 4 rai | 6,400 m² |
| 5 rai | 8,000 m² |
| 6 rai | 9,600 m² |
| 7 rai | 11,200 m² |
| 8 rai | 12,800 m² |
| 9 rai | 14,400 m² |
| 10 rai | 16,000 m² |
| 12 rai | 19,200 m² |
| 15 rai | 24,000 m² |
| 20 rai | 32,000 m² |
| 25 rai | 40,000 m² |
| 30 rai | 48,000 m² |
| 40 rai | 64,000 m² |
| 50 rai | 80,000 m² |
| 60 rai | 96,000 m² |
| 70 rai | 112,000 m² |
| 75 rai | 120,000 m² |
| 80 rai | 128,000 m² |
| 90 rai | 144,000 m² |
| 100 rai | 160,000 m² |
Where you’ll use it
Thai title deeds (chanote) and land office documents state area in rai, ngan and square wah, while architects, engineers and foreign buyers usually work in square meters. Converting the deed area into square meters is the starting point for site plans, building coverage calculations and price comparisons. A plot shown as 1-2-50 on a deed is 1 rai, 2 ngan and 50 square wah, which is 2,600 m².
Tip: Read the three numbers on a Thai deed separately: multiply rai by 1,600, ngan by 400 and square wah by 4, then add. Do not treat “1-2-50” as a decimal number of rai.