Meters to Wa (Thai) (m to wa)

1 meter equals 0.5 wa (Thai) exactly.

1 meter = 0.5 wa (Thai)

How to convert meters to wa (Thai)

To convert meters to wa (Thai), multiply the number of meters by 0.5. This factor is exact. To go the other way, multiply wa (Thai) by 2.

wa (Thai) = meters × 0.5

Example: 10 meters = 5 wa (Thai).

About these units

Meter (m)

Metric (SI)Current unit

The SI base unit of length. Since 1983 it is defined as the distance light travels in a vacuum in 1/299,792,458 of a second.

Meter comes from the Greek metron, a measure. In 1791 the French National Assembly defined it as one ten-millionth of the distance from the equator to the North Pole along a great circle through Paris, after rejecting the length of a seconds pendulum because that length changes with local gravity. The surveyors Delambre and Méchain measured the meridian arc, and in 1799 a platinum bar known as the Mètre des Archives became the physical standard. NIST notes that this Earth-based meter turned out to be about 0.2 mm shorter than the true pole-to-equator fraction it was meant to represent.

The 1875 Treaty of the Meter created the CGPM and the BIPM to look after common standards, and in 1889 a platinum-iridium prototype bar took over; the original is still kept at the BIPM. In 1960 the meter was tied to 1,650,763.73 wavelengths of an orange-red krypton-86 line, and in 1983 to the speed of light, which made length a quantity derived from the time standard. The 2018 revision reworded that definition without changing the meter's size. NIST offers a handy yardstick for scale: a pace, meaning two steps, is roughly a meter or a yard.

The meter is the reference unit for length on this site.

Sources: BIPM: history of the metre; NIST: the meter and the SI redefinition; Wikipedia: Metre

Wa (Thai) (wa)

ThaiTraditional unit (still used in some regions)

Exactly 2 meters, the Thai fathom. Used in land measurement alongside the rai.

Wa is the Thai fathom, a length of 2 meters. It belongs to a traditional Thai scale built on the human body, in which the khuep (span) is 25 cm, the sok (cubit) is 50 cm, and four sok make one wa, the span of outstretched arms.

Larger distances were counted in the sen, which is 20 wa, and the long road measure yot, equal to 400 sen. Surveyors working on the Royal Thai Survey Department cadastral survey, begun in 1896, tied these units to metric lengths, and the wa kept the round value of 2 m that it carries today.

Because the metric figure is exact, the old body-based uncertainty has gone. A wa still appears in land deeds and frontage descriptions, and in daily speech a plot may be described as so many wa wide. It is also the side of the square wa, which is 4 square meters.

1 wa (Thai) = 2 meters (exactly).

Sources: Wikipedia: Thai units of measurement; Wikipedia: Rai (unit)

Related conversions

See all length units.