Conversion

US Gallons to US Fluid Ounces Converter

1 US gallon = 128 fl oz. Enter any value to convert US gallons (gal) to US fluid ounces (fl oz), or use the table below for common values.

Results

1 gal =128 fl ozUS gallons → US fluid ounces
1 gal128 fl oz
1 fl oz0.0078125 gal
Formula
fl oz = gal × 128
1 gal in other units
1 gal in other units
UnitValue
milliliters (mL)3,785.411784
liters (L)3.785411784
cubic meters (m³)0.003785411784
US teaspoons (tsp)768
US tablespoons (tbsp)256
US fluid ounces (fl oz)128
US cups (cup)16
US pints (pt)8
US quarts (qt)4

Formula

fl oz = gal × 128

Example: 10 gal = 1,280 fl oz. To convert the other way, use gal = fl oz × 0.0078125.

Quick mental estimate: multiply by about 130.

US Gallons to US Fluid Ounces conversion table

US Gallons (gal)US Fluid Ounces (fl oz)
1 gal128 fl oz
2 gal256 fl oz
3 gal384 fl oz
4 gal512 fl oz
5 gal640 fl oz
6 gal768 fl oz
7 gal896 fl oz
8 gal1,024 fl oz
9 gal1,152 fl oz
10 gal1,280 fl oz
15 gal1,920 fl oz
20 gal2,560 fl oz
25 gal3,200 fl oz
30 gal3,840 fl oz
40 gal5,120 fl oz
50 gal6,400 fl oz
75 gal9,600 fl oz
100 gal12,800 fl oz
250 gal32,000 fl oz
500 gal64,000 fl oz
1,000 gal128,000 fl oz

About US gallons and US fluid ounces

The US gallon is exactly 231 cubic inches, about 3.785 liters. Fuel and milk are sold by the gallon in the US; the UK imperial gallon is about 4.546 liters.

The US fluid ounce is 1/128 of a US gallon, about 29.57 mL. It is used on drink and cosmetics labels in the US.

Other Volume conversions

Frequently asked questions

How do I convert US gallons to US fluid ounces?

Use the formula fl oz = gal × 128. For example, 10 gal = 1,280 fl oz.

What is 1 US gallon in US fluid ounces?

1 gal = 128 fl oz.

How do I convert US fluid ounces back to US gallons?

Use gal = fl oz × 0.0078125. 1 fl oz = 0.0078125 gal.