Forties to Fluid Ounces Converter

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

forties
Result
0 fluid ounces

Common Forties to Fluid Ounces Conversions

Forties Fluid Ounces
1 forty40 fl oz
2 forties80 fl oz
3 forties120 fl oz
5 forties200 fl oz
10 forties400 fl oz
15 forties600 fl oz
20 forties800 fl oz
25 forties1000 fl oz
50 forties2000 fl oz

How to Convert Forties to Fluid Ounces

Converting forties to fluid ounces is the most straightforward conversion in beer volume measurements. A forty is named specifically for its 40 fluid ounce capacity, making this a simple multiplication.

The Conversion Formula

The formula to convert forties to fluid ounces is simple:

fluid ounces = forties x 40

This formula works because one forty equals exactly 40 fluid ounces by definition. This is the simplest conversion possible with a 1:40 ratio.

Example 1: Converting 5 Forties to Fluid Ounces

fluid ounces = 5 x 40

Result: 200 fl oz

Example 2: Converting 25 Forties to Fluid Ounces

fluid ounces = 25 x 40

Result: 1000 fl oz

What Is a Forty?

A forty (also written as "40" or "40 oz") is a glass or plastic bottle containing exactly 40 US fluid ounces of beer, approximately 1.18 liters. The name "forty" comes directly from its fluid ounce measurement. This bottle size became popular in the United States, particularly for malt liquor and certain domestic beer brands.

What Is a Fluid Ounce?

A US fluid ounce (fl oz) is a unit of liquid volume equal to approximately 29.57 milliliters. It is one of the basic units of volume in the US customary measurement system. One fluid ounce is 1/128 of a US gallon or 1/8 of a cup. The fluid ounce should not be confused with the ounce used for weight measurement.

Why Convert Forties to Fluid Ounces?

This conversion is useful for:

Quick Reference

Key conversion facts: