Posted on 12th Apr 2011 @ 2:34 PM

Shaku-Sun System

The old Japanese system of measurement was based on the “Shaku” and “Sun” (pronounced like “soon.”) All manner of objects were measured with this system, including swords, kendo armor and shinai, and clothing.

1 shaku = 10 sun = 100 bu = 1000 rin

For ordinary objects, in architecture and constructed products, the “Kane-jaku” is employed. (“kane” in Japanese is 'metal,' its meaning is “the metal-shaku.”)

One kanejaku is approximately equal to 30.3 centimeters.

A sun being one-tenth of a shaku, is approximately 3.03 centimeters.

To convert centimeters to shaku/sun, divide your measurement by 30.3.

For example 120 cm divided by 30.3 equals 3.9+, or 3 shaku, 9 sun (a “39” shinai.)

A special case for cloth, such as in keiko-gi and hakama, the “Kujira-shaku” is used. Interestingly enough, in pre-modern times, whale whiskers were used for measuring cloth. The word for whale is kujira.

One kujira-shaku is approximately equal to 37.9 centimeters.

A sun being one-tenth of a kujira-shaku, is approximately 3.79 centimeters.

To convert centimeters to kujira-shaku, divide your measurement by 37.9.

For example, 91 centimeters divided by 37.9 equals 2.4, or 2 shaku, 4 sun, the same as a “24” hakama.