Forties to Gallons Converter

Convert volume measurements from forties (40 oz bottles) to gallons quickly and accurately. Enter any forties value and get the equivalent in US gallons.

forties
Result
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Common Forties to Gallons Conversions

Forties Gallons
1 forty0.3125 gallons
2 forties0.625 gallons
3.2 forties1 gallon
5 forties1.5625 gallons
10 forties3.125 gallons
16 forties5 gallons
20 forties6.25 gallons
32 forties10 gallons
50 forties15.625 gallons

How to Convert Forties to Gallons

Converting forties to gallons is useful for understanding beer volumes in standard US liquid measurement terms. A forty contains 40 fluid ounces of beer, while a US gallon contains 128 fluid ounces.

The Conversion Formula

The formula to convert forties to gallons is based on their fluid ounce equivalents:

gallons = forties x (40 / 128)

This formula works because one forty equals 40 fluid ounces, and one US gallon equals 128 fluid ounces. The conversion factor is 0.3125, meaning each forty is exactly 5/16 of a gallon.

Example 1: Converting 5 Forties to Gallons

gallons = 5 x (40 / 128)

gallons = 5 x 0.3125

Result: 1.5625 gallons

Example 2: Converting 16 Forties to Gallons

gallons = 16 x (40 / 128)

gallons = 16 x 0.3125

Result: 5 gallons

What Is a Forty?

A forty (also written as "40" or "40 oz") is a glass or plastic bottle containing 40 fluid ounces of beer, approximately 1.18 liters. This bottle size is popular for malt liquor and certain domestic beer brands. Each forty represents about 0.31 gallons of liquid.

What Is a US Gallon?

A US gallon is a unit of liquid volume equal to 128 fluid ounces, 4 quarts, 8 pints, or approximately 3.785 liters. The US gallon is different from the Imperial gallon used in the UK and Canada (which is approximately 4.546 liters). The gallon is commonly used for measuring larger liquid quantities in the United States.

Why Convert Forties to Gallons?

This conversion is useful for:

Quick Reference

Key conversion facts: