Skip to main content
LibraTool logoLibraTool

Free Thai Land Area Converter (Rai, Ngan, Tarang Wah)

Convert Thai land units (rai, ngan, tarang wah / sq wah) to and from square metres, hectares, square feet and acres. Enter a plot in rai-ngan-wah notation (e.g. 1-2-50) to get the total area, or format any area back into Thai notation. Exact 1923-standard factors, instant conversion, fully private in your browser.

Works offline once loaded

Thai notation: rai-ngan-wah

Type a plot as written on the deed (e.g. 1-2-50) or fill the three boxes. You get the area in every unit below.

2,600m² total
= 1-2-50 (rai-ngan-wah)

Result in all units

Some Thai deeds print wah as a decimal fraction (for example 0-1-23.5). Enter it as is; decimals are accepted in every field.

Price calculator

Optional: enter a listing price to see the total and the price per rai, ngan, sq wah, m², sq ft and acre. It applies to the area you edited last. The currency is only a label; no exchange rates are used.

Result
1,600
1 rai = 1,600 m²
As rai-ngan-wah:(1 rai, 0 ngan, 0 wah)

1 rai in all units

Add plots and divide into lots

Add neighbouring plots from a deed (each as rai-ngan-wah or an area in any unit) to get the total, then split it into equal lots.

1.
2.
Total area of all plots
2,600 m²
Each of 3 lots
216.67 tarang wah · 866.67 m²

Rectangle plot (width x length)

Measured a plot? Enter street frontage and depth to get the area in rai-ngan-wah, sq wah, m² and sq ft.

800 m² · 200 tarang wah
Frontage: 20 m = 10 wah = 65.6168 ft
Depth: 40 m = 20 wah = 131.23 ft
Depth is 2 times the frontage
Thai land unit reference
1 rai (ไร่)1,600 m² = 4 ngan = 400 tarang wah
1 ngan (งาน)400 m² = 100 tarang wah
1 tarang wah (ตารางวา)4 m² (2 m × 2 m)
1 rai≈ 17,222.26 sq ft ≈ 0.3954 acre = 0.16 ha
1 hectare= 6.25 rai
1 acre≈ 2.529 rai
Exact, with one caveat. Thailand standardised rai, ngan and tarang wah against the metric system in 1923, so the conversions to square metres and hectares are exact. The square-foot and acre values are derived from the international foot and are rounded for display (marked ≈). For legal or title purposes, always use the official figures on the land deed (chanote).

Everything is computed locally in your browser. No values are uploaded or stored.

How It Works

This converter handles every Thai land unit in two ways: a normal from/to picker for single-unit conversions, and a dedicated rai-ngan-wah triplet input that matches how plots are actually written on Thai land deeds. The Thai system was standardised against the metric system in 1923, so conversions to square metres and hectares are exact rather than approximate.

  1. 1
    Pick units and enter an amount
    Type a number, choose the unit you have (rai, ngan, tarang wah, m2, hectare, sq ft or acre) and the unit you want. The result updates live, and a swap button flips the two units instantly.
  2. 2
    Or enter rai-ngan-wah
    Use the three boxes to enter a plot the Thai way, e.g. 1-2-50 (1 rai, 2 ngan, 50 wah). You get the total square metres plus the canonical rai-ngan-wah notation, normalised if your ngan or wah exceed their limits.
  3. 3
    See every unit at once
    Each conversion expands into a tile grid showing the area in all seven units, with Thai script labels. Any area is also formatted back into rai-ngan-wah notation so you can read it the local way.
  4. 4
    Copy or share
    Tap any value tile to copy it, copy the full result line, or share a link that reproduces your exact inputs. Imperial values (sq ft, acre) are marked with the approximately-equal sign because they round for display.

Every calculation runs locally in your browser using JavaScript. No numbers, plot sizes, or land details are ever uploaded, logged, or stored on a server.

Related Tools

📐

Bangladesh Land Area Converter (Katha, Bigha, Shotok)

Instantly convert Bangladeshi land units - katha, bigha, shotok (decimal), kani, gonda, ojutangsho - to and from square feet, square metres and acres using the Ministry of Land standard. Bengali labels, regional kani/bigha presets, and a reference table included.

Try it
🌾

Indian Land Area Converter

Convert bigha, katha, biswa, guntha, cent, marla, kanal, ground and more to square feet, gaj, acre, hectare — with the correct state-wise value for units that vary by region.

Try it
🏗️

Pakistan Land Area Converter (Marla, Kanal, Killa)

Convert Pakistani land units - marla, kanal, killa (acre), murabba, sarsai - to square feet, square yards (gaz) and square metres. Includes a marla-standard selector (272.25, 250 or 225 sq ft) so you never mix up Lahore housing-scheme marlas with the official standard.

Try it

Frequently Asked Questions