How Many Ounces in a Gallon?
There are 128 fluid ounces in a US gallon and 160 fluid ounces in a UK (imperial) gallon.
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Formula
Answer: There are 128 fluid ounces in a US gallon and 160 fluid ounces in a UK (imperial) gallon.
Example
Question: How many ounces in a gallon? Answer: There are 128 fluid ounces in a US gallon and 160 fluid ounces in a UK (imperial) gallon.
How to Use
- Read the direct answer at the top of the page
- Check the conversion table for common values
- Use the related converter for custom values
- Browse the FAQ for common follow-up questions
Frequently Asked Questions
How many water bottles in a gallon?
A standard 16.9 oz water bottle means about 7.57 bottles per gallon. A 8 oz bottle means 16 bottles per gallon.
How many ounces in a half gallon?
There are 64 fluid ounces in a half gallon (US).
Is a fluid ounce the same as a weight ounce?
No. A fluid ounce measures volume (29.57 ml), while a weight ounce measures mass (28.35 g). They differ for most substances.