US Gallons to Koku (gal to koku)

1 US gallon equals 0.0209845193 koku (rounded).

1 US gallon = 0.0209845193 koku

How to convert US gallons to koku

To convert US gallons to koku, multiply the number of US gallons by 0.0209845193. The factor is rounded to 10 significant digits. To go the other way, multiply koku by 47.65417714 (rounded).

koku = US gallons × 0.0209845193

Example: 10 US gallons = 0.209845193 koku.

Pints, quarts, gallons and fluid ounces differ between the US and the UK. Units are labeled 'US' or 'imperial' to avoid confusion.

About these units

US Gallon (gal)

US customaryCurrent unit

Exactly 231 cubic inches or 3.785411784 liters (128 US fluid ounces). About 17% smaller than the imperial gallon.

The US gallon is a survivor of English wine trade. Around 1706, a statute in Queen Anne's reign fixed the wine gallon at exactly 231 cubic inches, settling confusion among the competing gallons for wine, ale and corn. British colonies in North America used that wine gallon, and in 1824 Britain replaced all its gallons with a new imperial one while the United States kept the old measure. It was adopted as the legal US standard in 1836 and is still defined as exactly 231 cubic inches, or 3.785411784 liters.

That makes the US gallon about 17 percent smaller than the imperial gallon, a difference that explains why American and British fuel-economy figures cannot be compared directly. Everyday uses are milk jugs, paint cans and gasoline pumps. One gallon divides evenly into four quarts, eight pints, sixteen cups and 128 fluid ounces. A gallon of water weighs a little over 8 pounds, an easy figure to remember when loading a car with water jugs.

1 US gallon = 3.785411784 liters (exactly).

Sources: Wikipedia: Gallon; NIST SP 811, Appendix B.8: conversion factors for volume

Koku (koku)

JapaneseHistorical unit (no longer in standard use)

One hundred shō, about 180.39 L. The amount of rice thought to feed one person for a year; feudal domains were ranked by their koku.

Rice decided rank in Tokugawa Japan, and the koku was the yardstick. A domain whose assessed income reached 10,000 koku could have a daimyo as its lord, and the Kaga domain, rated at about 1.025 million koku, was famous as the million-koku domain. The assessment was a notional yield, with other crops converted to their rice value, and real revenue averaged only around 40 percent of it.

One koku was commonly taken as enough rice to feed one person for a year, though a merchant house code cited in the sources allowed about 1.8 koku per man, so the rule of thumb is loose. The unit equals 10 to, 100 sho or 1,000 go, and it descends from the Chinese dan, which was about 59 litres under the Tang dynasty.

The Meiji law of 1891 fixed the sho from the old kyo-masu measuring box at 2401/1331 litre, which makes the koku about 180.39 litres, close to 5 bushels. Shipping and timber koku were different quantities. A lumber koku is about 278 litres, so the word always needs its context.

1 koku = 180.3906837 liters (approximately).

Sources: Wikipedia: Koku; Wikipedia: Kokudaka; Wikipedia: Japanese units of measurement

Related conversions

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