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Convert US gallons to US fluid ounces

Convert US gallons (gal) to US fluid ounces (fl oz). 1 gal = 128 fl oz, and 1 fl oz = 0.0078125 gal.

1 gal = 128 fl oz

Gallons to Fluid Ounces formula

fl oz = gal × 128

Multiply the number of US gallons by 128.

Example: To convert 1 gal to US fluid ounces: 1 × 128 = 128 fl oz.

Quick answers

What is 1 gal in US fluid ounces?
1 gal = 128 fl oz
What is 5 gal in US fluid ounces?
5 gal = 640 fl oz
What is 10 gal in US fluid ounces?
10 gal = 1,280 fl oz

Gallons to Fluid Ounces conversion table

Fluid Ounces to Gallons table
US gallons (gal)US fluid ounces (fl oz)
0.5 gal64 fl oz
1 gal128 fl oz
2 gal256 fl oz
3 gal384 fl oz
5 gal640 fl oz
10 gal1,280 fl oz
12 gal1,536 fl oz
15 gal1,920 fl oz
20 gal2,560 fl oz
25 gal3,200 fl oz
50 gal6,400 fl oz
55 gal7,040 fl oz
100 gal12,800 fl oz
500 gal64,000 fl oz
1,000 gal128,000 fl oz

Frequently asked questions

How many US fluid ounces are in a US gallon?

There are 128 US fluid ounces in a US gallon (1 gal = 128 fl oz).

How do I convert US gallons to US fluid ounces?

Multiply the number of US gallons by 128. To convert 1 gal to US fluid ounces: 1 × 128 = 128 fl oz.

Is the Gallons to Fluid Ounces conversion exact?

Yes. Both units are defined exactly, so 1 US gallon is exactly 128 US fluid ounces. Results on this page are rounded to six significant digits; pick more decimals in the converter if you need them.

What is 1 gal in US fluid ounces?

1 gal = 128 fl oz.

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

Use the reverse relationship: 1 fl oz = 0.0078125 gal. The Fluid Ounces to Gallons page has a converter and a full table.

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