US Fluid Ounces to Koku (fl oz to koku)

1 US fluid ounce equals 0.000163941557 koku (rounded).

1 US fluid ounce = 0.000163941557 koku

How to convert US fluid ounces to koku

To convert US fluid ounces to koku, multiply the number of US fluid ounces by 0.000163941557. The factor is rounded to 10 significant digits. To go the other way, multiply koku by 6,099.734674 (rounded).

koku = US fluid ounces × 0.000163941557

Example: 10 US fluid ounces = 0.00163941557 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 Fluid Ounce (fl oz)

US customaryCurrent unit

One 128th of a US gallon, 29.5735 mL. Not the same as the weight ounce, and about 4% larger than the imperial fluid ounce.

Fluid ounce began as an attempt to link volume to weight: the volume occupied by one ounce of some substance, such as wine in England or water in Scotland. Definitions varied by region and by liquid. When Britain defined its imperial gallon in 1824 as the space of ten pounds of water, the imperial fluid ounce came out so that an ounce of water weighs about one avoirdupois ounce. The US fluid ounce followed a different path and comes from the older wine gallon.

The US fluid ounce is exactly 1/128 of a US gallon, 29.5735295625 milliliters, about 4 percent bigger than the imperial one at 28.4130625 milliliters. American nutrition labels use yet another figure, treating one fluid ounce as 30 milliliters, a convenient rounding for serving sizes. The name is a trap, because a fluid ounce measures space while a weight ounce measures mass. A US fluid ounce of water weighs a bit more than an ounce of weight, while a fluid ounce of honey weighs considerably more.

1 US fluid ounce = 0.02957352956 liters (approximately).

Sources: Wikipedia: Fluid ounce; NIST SP 811, Appendix B.8: conversion factors for volume; 21 CFR 101.9: nutrition labeling household measures

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

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