Acre-feet to US Fluid Ounces (ac⋅ft to fl oz)

1 acre-foot equals 41,708,982.86 US fluid ounces (rounded).

1 acre-foot = 41,708,982.86 US fluid ounces

How to convert acre-feet to US fluid ounces

To convert acre-feet to US fluid ounces, multiply the number of acre-feet by 41,708,982.86. The factor is rounded to 10 significant digits. To go the other way, multiply US fluid ounces by 2.39756506×10⁻⁸ (rounded).

US fluid ounces = acre-feet × 41,708,982.86

Example: 10 acre-feet = 417,089,828.6 US fluid ounces.

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

Acre-foot (ac⋅ft)

US customaryTraditional unit (still used in some regions)

The volume of water that covers one acre to a depth of one foot: 43,560 cubic feet or about 1,233.48 cubic meters. Used for reservoirs and irrigation in the US.

Water engineers in the western United States took the acre, a land measure of 43,560 square feet that began as a strip one chain by one furlong, and gave it a depth of one foot to describe water. The result, the acre-foot, covers 43,560 cubic feet, which is about 1,233.48 cubic meters or roughly 1.23 million liters. In US gallons it comes to about 325,851.

The unit is used for reservoirs, canals, aqueducts, irrigation allotments and river flows, where the volumes are too large for gallons to be comfortable. A common planning rule treats one acre-foot per year as the water use of a suburban household, although Santa Fe households average closer to a quarter of that.

The size depends slightly on which foot is used. The figure used here follows the international foot of exactly 0.3048 m. The older US survey foot makes the unit about 0.0006 percent larger, a gap that matters little in practice. Most other countries state such volumes in cubic meters, megaliters or cubic kilometers.

1 acre-foot = 1,233,481.838 liters (approximately).

Sources: Wikipedia: Acre-foot; Wikipedia: Acre

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

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