The shō, Japanese unit of volume
The shō is 1.8039 liters, that is ten gō. It is the measure of rice and sake, and the capacity of the bottle Japan calls the isshōbin.
Its value is not arbitrary, it is a shape. The masu was a square box 4.9 sun on a side and 2.7 sun deep, that is 64.827 cubic sun. Since the sun is a thirty-third of a meter, that volume comes to 2401 liters divided by 1331, seven to the fourth over eleven cubed, and metrication copied the ratio rather than rounding it. The box outlived its own removal from commercial deeds: the isshōbin, the 1.8 liter bottle, remains the format for sake, soy sauce and vinegar, deposited and refilled.
The shō in other units
| 1 sho | 0.00180391 m³ |
| 1 sho | 1.80391 l |
| 1 sho | 180.391 cl |
| 1 sho | 1,804 ml |
| 1 sho | 0.476542 gal |
| 1 sho | 0.396804 gal UK |
| 1 sho | 3.81233 pt |
| 1 sho | 60.9973 fl oz |
| 1 sho | 63.4886 fl oz UK |
| 1 sho | 1.90617 qt |
| 1 sho | 1.58722 qt UK |
| 1 sho | 3.17443 pt UK |
| 1 sho | 7.62467 cup |
| 1 sho | 7.21563 cup metric |
| 1 sho | 9.01953 cup JP |
| 1 sho | 121.995 tbsp |
| 1 sho | 120.26 tbsp metric |
| 1 sho | 90.1953 tbsp AU |
| 1 sho | 365.984 tsp |
| 1 sho | 360.781 tsp metric |
| 1 sho | 18.0391 dl |
| 1 sho | 0.0113462 bbl |
| 1 sho | 10 go |
Frequently asked questions
What are the to and the koku?
The two steps above the shō: ten shō make one to, 18.039 liters, and ten to one koku, 180.39 liters. The koku is the one that mattered, because it served as a measure of wealth rather than of volume. A fief was rated by the koku of rice its land yielded, one koku being taken as an adult's yearly ration, and the Kaga domain was famed as a million koku, that is 180,391 cubic meters of rice.
Is the timber koku the same koku?
No, and it is half as large again. The building koku is ten cubic shaku, 0.2783 cubic meter, where the rice koku is 0.1804: a ratio of 1.54 under one word. Japanese structural timber is still sold by the koku, and an invoice that does not say which one is out by half.
Are the Chinese sheng and the Korean doe shō?
The Korean doe is, Korea having taken over the Japanese measure and its 1.8039 liters. The Chinese sheng is not: metrication made it the liter itself, and the character 升 is now the ordinary Chinese word for liter. The same sign is therefore 1.8 liters in Tokyo and 1 liter in Beijing, a factor of 1.8 on a label of imported rice or sake.