Thai Area Converter: Convert Rai, Ngan and Tarang Wa to Square Meters, Acres and Hectares

Browse any Thai land listing and you will quickly meet a compact string like 2-1-50. To a newcomer it looks like a serial number, but it is actually rai-ngan-wa notation — the everyday shorthand Thais use for land area. Without decoding it, you cannot tell whether a plot is a generous orchard or a modest building lot. Our Thai Area Converter decodes the notation and translates it into square meters, square feet, acres and hectares.

The tool is built for real transactions. Enter any amount of rai, ngan or tarang wa — individually or combined — and you instantly get the full picture in metric and imperial units, plus a clean breakdown you can paste into a contract annex or a bilingual listing. Everything runs 100% client-side: no sign-up, no upload, no waiting.

Why Use the Thai Area Converter?

• It decodes combined notation instantly. Listings rarely quote plain rai; they quote values like 2-1-50, meaning 2 rai, 1 ngan and 50 tarang wa. The converter reads the three parts, sums them, and shows the breakdown and the total.
• It speaks metric and imperial fluently. Results arrive in square meters, square feet, acres and hectares at once.
• It uses exact, standard constants. One acre is exactly 4,046.8564224 square meters and one hectare exactly 10,000 — no shortcuts that drift on large parcels.
• It protects your privacy. The conversion is 100% client-side: nothing you type ever leaves your device.
• It is free and unlimited. No account, no paywall, no daily cap.
• It works everywhere. The page is lightweight and responsive on phone and desktop alike.

Key Features

• One tool, three entry points. Whether a document quotes only rai, a contractor quotes tarang wa, or a listing uses the combined 2-1-50 style, you enter it directly.
• Numbers stay consistent across units. Every output derives from the same base figure in square meters, so the acre, hectare and square-foot values always agree — ideal when one contract quotes several units.
• Readable for non-specialists. Each Thai unit is labeled in plain English, so a first-time buyer can follow along.

How to Use the Thai Area Converter

1. Open the tool. Navigate to the Thai Area Converter page.
2. Choose your input unit. Pick rai, ngan, tarang wa, square meters, square feet, acres or hectares.
3. Enter the amount. Type the number from your document or listing; for combined notation, enter each part in its own field.
4. Read the full breakdown. The tool shows the total in square meters, square feet, acres and hectares, and restates the plot in rai-ngan-wa form.
5. Copy what you need. Drop the figures into your listing, spreadsheet, or contract annex.

The Rai-Ngan-Wa System

Thai land measurement rests on three units stacked in a neat ladder. The smallest is the tarang wa — literally a square wa — and since one wa is two meters, a tarang wa is a 2-by-2-meter square: 1 tarang wa = 4 square meters. Stack one hundred and you have 1 ngan = 100 tarang wa = 400 square meters, roughly a single house plot. Four ngan make 1 rai = 4 ngan = 1,600 square meters, the workhorse unit for fields and large parcels.

When a listing reads ร-ง-ว 2-1-50, read the three digits left to right: first rai, then ngan, then tarang wa. So 2-1-50 means 2 rai (2 × 1,600 = 3,200 m²) plus 1 ngan (400 m²) plus 50 tarang wa (50 × 4 = 200 m²), a total of 3,800 square meters — about 0.38 hectare or roughly 0.94 acre. Position matters: 1-2-50 works out to 1,600 + 800 + 200 = 2,600 square meters. Small plots drop leading zeros, so a lot written 0-0-80 is simply 80 tarang wa, or 320 square meters.

For international orientation, one acre is about 2.53 rai, and one hectare is exactly 6.25 rai, because 10,000 divided by 1,600 is 6.25. Working the other way, 1 rai is about 0.4 acre, exactly 0.16 hectare, and roughly 17,222 square feet. A full-size football pitch sits near 4.5 rai — a handy anchor when a listing says 5 rai.

This notation is officialdom, not folklore. Title deeds — the chanote, formally Nor Sor 4 Jor — state area in rai-ngan-wa, as do Nor Sor 3, land tax notices, and virtually every Thai-language listing. If a foreign brochure quotes acres while the chanote quotes rai-ngan-wa, the chanote governs.

Practical Use Cases

Foreign Buyers Reading Thai Land Listings

A 2-1-50 beachfront plot sounds modest until you realize it is 3,800 square meters, while a 0-2-0 town plot is only 800. Converting before you fall in love with a listing keeps expectations realistic and lets you compare price per unit of area across provinces.

Real-Estate Agents Preparing Bilingual Materials

Agents serving international clients constantly translate between systems. Quoting both notations — "2-1-50 (3,800 sq m / 0.94 acre)" — builds trust and cuts back-and-forth questions, while keeping the Thai notation exact.

Agricultural Planning and Farm Management

Farm budgets in Thailand are built per rai: seed, fertilizer, water and yield all quoted per rai. If a consultant recommends 20 kilograms of fertilizer per rai and your orchard measures 6-2-0, converting to 10,400 square meters — 6.5 rai — tells you exactly how much to buy.

Construction Site Sizing and Development

Builders think in square meters and planning codes in plot ratios, while the deed speaks rai. Sizing a warehouse on a 1-1-0 site (2,000 square meters) or a resort across 10 rai (16,000 square meters) starts with one honest conversion; setbacks and floor-area calculations follow.

Best Practices

• Always quote both notations in contracts. Write the rai-ngan-wa figure and the square-meter figure side by side, so neither party can later claim a translation error.
• Verify against the chanote. The title deed is the authoritative record. Confirm that the quoted area matches before money changes hands.
• Beware rounding in listings. Marketing copy often rounds to the nearest half rai or converts loosely to acres. A half-rai error on a large parcel is 800 square meters.
• Do not mix units mid-calculation. Convert everything to square meters first, then derive acres or hectares, to avoid compounding rounding errors.
• Remember that a wa is two meters. A tarang wa is a 2-by-2-meter square, not a meter squared; treating one wa as one square meter understates area fourfold.
• Use exact constants when money is involved. For price-per-acre valuations, use the tool's exact figures — an acre is 4,046.8564224 m², a hectare 10,000 m².

Start Converting Thai Land Areas Today

Whether you are comparing beachfront parcels in Phuket, sizing an orchard in Chiang Mai, or preparing a bilingual brochure, the Thai Area Converter turns rai, ngan and tarang wa into numbers you can act on — instantly, accurately, and entirely on your own device. Enter the numbers from your next listing and see the plot in square meters, acres and hectares.

Related Tools You Might Like

• Unit Converter — Convert length, weight, volume, temperature and many other units in one place.
• Height Converter — Switch between centimeters, feet and inches instantly.
• Rent vs Buy Calculator — Weigh renting against buying a home with a full cost comparison.

Happy converting!

Frequently Asked Questions

Q: How many square meters is one rai? A: One rai is exactly 1,600 square meters. It divides into 4 ngan, and each ngan is 100 tarang wa, so one rai also equals 400 tarang wa.

Q: What does 2-1-50 mean in a Thai land listing? A: It is rai-ngan-wa notation: 2 rai, 1 ngan and 50 tarang wa — 3,800 square meters in total, about 0.38 hectare or 0.94 acre.

Q: How many rai are in an acre or a hectare? A: One acre is approximately 2.53 rai, and one hectare is exactly 6.25 rai. Conversely, one rai is about 0.4 acre and exactly 0.16 hectare.

Q: Is a tarang wa the same as a square wa? A: Yes. A wa is two meters, so a tarang wa — literally a square wa — is a 2-by-2-meter square of 4 square meters.

Q: Does the converter upload my numbers anywhere? A: No. The tool is 100% client-side: every calculation happens in your browser, and no input is stored or transmitted.