The Japanese (Shakkanhō) Volume equation converts volumes in Japanese units to modern (Western) volumes such as litres based on conversion conventions in place since 1891. It is used to measure both dry and liquid volume.

Introduction

The base unit of volume in the Shakkanhō system is the Shō. The Shō and its denominations are equivalent to the following metric measurements:

• Sai (才) = 1.804mL
• Shaku (勺) = 18.04mL
• Gō (合) = 180.4mL
• Shō (升) = 1.804L
• To (斗) = 18.04L
• Koku (石) = 180.4L

Further Notes

Other Japanese units of measurement, such as those used for rice weight measurements, may share the same names as the units used for volume. Furthermore, since the Japanese language contains many homonyms some units for measuring length, area, weight and mass, are romanized in the same manner as those above, but use different kanji (Chinese characters) to distinguish between them. One example is the Shaku, which when used to measure length is written with the character 尺. 

Japanese (Shakkanho) Unit Conversion Calculators

• Japanese Area - Shaku(勺), Go(合), Jo(畳), Tsubo(坪), Bu(歩), Se(畝), Tan (段 or 反), and Chō or Chōbu (町 and 町歩).
• Japanese Lengths - Mō (毛 or 毫), Rin (厘), Bu (分), Sun (寸), Shaku (尺), Ken (間), Hiro (?), Jō (丈), Chō (町), and Ri (里).
• Japanese Volume (Dry and Liquid) - Sai (才), Shaku (勺), Gō (合), Shō (升), To (斗), and Koku (石).
• Japanese Weight and Mass - Mō (毛 or 毫), Rin (厘), Bu (分), Monme or Momme (匁), Ryō (両), Hyakume (百目), Kin (斤), Kan or Kanme (貫 and 貫目), Maru (丸), and Tan (担 or 擔).
• Japanese Rice Weights - Shaku (勺), Gō (合), Shō (升), To (斗), Hyō (俵), and Koku (石).