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Thai measurements

I would like to express my thanks to my wife for giving me the idea to build this page, to my Thai and Thai resident friends for their valuable assistance and feedback. Additional information is referenced at the bottom of the page.

In 1923 Thailand went metric even today some traditional units remain in common use. Area measurements are in use today as are some length measurements used in construction. The odd volume or weight unit are popular in pharmacies and farming communities.


Length

Cadastral plans use a scale of 1:4,000 (1 centimetre when plotted on paper equals one sen which is 40 metres or 4,000 centimetres).

Picture of a sliderule

Anthropic meanings of some length measurements are:

  • Krabiat - Quarter of a finger
  • Nio - Finger
  • Khuep - Span
  • Sawk - Cubit (middle finger to elbow)
  • Wah - Outstretched arms
Metric Thai
Centimetre
Metre
Kilometre
Krabiat Nio Khuep Sawk Wah Sen Yoht
0.521 cm 1 - - - - - -
2.083 cm 4 1 - - - - -
25 cm 48 12 1 - - - -
50 cm 96 24 2 1 - - -
2 m 384 100 8 4 1 - -
40 m 7,680 1,920 160 80 20 1 -
16 km - - - 32,000 8,000 400 1
 Length calculations  Picture of notebook

Usage: For calculations select the desired unit. Enter a numeric digit in the quantity field click anywhere outside of the input field or use the up down buttons.

Tip: To keep a history of your measurements use notes, if your browser has local storage enabled they will be available when you visit next time.


Area

Official documents relating to land express size in three main units of area. This can cause confusion. Requiring the use of google especially for foreigners residing in Thailand. Documents show a column layout expressed as rai, ngan, and tarang wah with numbers or fractions in the corresponding column below.

Rai Ngan Tarang wah
0 0 21310

This would be equal to 85.20 square meters.

Anthropic meaning:

  • Tarang wah - Squared (outstretched arms)
Metric Thai
Square metre Tarang Wah Ngan Rai
4 m² 1 0.01 0.0025
400 m² 100 1 0.25 
1600 m² 400 4 1
 Area calculations  Picture of notebook

Note: To approximately express an acre (4,046.86 m²) in Thai "two rai two ngan and eleven seventenths tarang wah ".


Weights

Salueng and baht are still commonly used today in purchasing herbal medicines and gold. Other weights are not as common and often metric is used, occasionally in combination with traditional units.

Picture of old scale weights
Metric Thai
Grams
Kilograms
Salueng Baht Tamlung Chang Haap
3.75 g 1 - - - -
15 g 4 1 - - -
60 g 16 4 1 - -
1200 g (1.2 kg) 320 80 20 1 -
60,000 g (60 kg) 16,000 4,000 1000 50 1
 Weight calculations  Picture of notebook

Note: Gold baht weight differs from 15g to 15.16g


Volume

Picture of an old wooden bucket

Volumes still in use by farmers include thang (bucket) and kwian (oxcart used for the transportation of grain or rice).

Metric Thai
Litres
Cubic metres
Thanan Thang Sat Ban Kwian
1 l 1 - - - -
20 l 20 1 - - -
25 l 25 1.25 1 - -
1,000 l (1 m³) 1,000 50 40 1 -
2,000 l (2 m³) 2,000 100 80 2 1
 Volume calculations  Picture of notebook


References

Links used to collate some information displayed.