An often asked question is "Why does sake made in Japan come in such unusual sizes such as 1800ml and 720ml?" The answer is quite simple: Sake continues to be regarded as a traditional product in Japan and is still bottled using the traditional Japanese measurement standards.
The traditional Japanese measurement system was originally based on a Chinese standard but was subject to regional differences which tended to change over time. It developed into a more unified form during the Edo period (1603-1868) when the merchant class grew in importance and trade and production was expanded within Japan. Officially separated from the rest of the world through the policy of the Tokugawa Shogunate, Japan measured, traded and sold liquid products through its unique system based on the "sho" (approximately 1800ml).
| Japanese Measure Unit |
Metric Equivalent (approximate) |
Usage | Image |
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18ml | A "sip" of sake, the shaku is commonly used to describe a slightly smaller size of the box-like masu cup. Known as the 8-shaku, this masu contains approximately 144ml. |  |
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180ml | This is the approximate amount that fits in the box-like masu cup and standard tokkuri pitcher. Considered a common serving size, the go has been an important unit for sake measurement. The 720ml sake size bottle is referred to as a "4-go" which represents approximately 4 single sake servings. |  |
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1800ml | At the beginning of the 20th century when glass bottling techniques were introduced to Japan, the sho was chosen as the standard bottle size. This bottle, known as the isshobin (1-sho bottle) continues to be the most popular bottle size in Japan. Many traditional sakaya (sake pubs) display the isshobin to show the range of their sake menu. |  |
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18L | The to is the common unit to describe the volume of sake barrels. The most common sake barrel size (72L) is referred to as the "4-to." The common medium size barrel (36L) is the "2-to" and the small size (18L) is the "1-to." |  |
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180L | This is the most common size for describing a sake brewing capacity. Even today, most brewers plan and describe their production not in liters but rather in koku. |  |