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How many Ounces in a Gallon? Here is everything you need to know on how to convert ounces to gallons. We will discuss some simple definitions and see all the differences between US and UK measurements. Stick around, because at the end of this guide you will find a free conversion chart!
Whether you’re baking for Thanksgiving or you’re scooping out ice cream on a hot summer day, you may come across the question “How many ounces are in 1 gallon?”. I know that getting your head around can be challenging some times, especially when we are cooking and need a quick & easy ounces to gallons conversion. I was there too, so I wrote this guide that will teach how to remember that one gallon is equal to 128 fluid ounces.
What is an ounce?
An Ounce is a common unit of measurement used in the United States and a few other countries to weight out small quantities, like ingredients. In recipes and cookbooks, you may often find ounce under the abbreviation of “oz”. The term “ounce” comes from the Latin “uncia” or “twelfth part”. In Ancient Rome, the “uncia” was a unit of measurement for both weights and lengths.
What is a gallon?
A Gallon is a unit of volume commonly used to measure liquids, especially in the United States and the United Kingdom. It originated from the Latin word “galleta” or “galletum,” meaning a pail or a bucket. Historically, the gallon was used to measure wine and beer, and it is nowadays utilized for measuring liquids. In the U.S., a gallon equals 128 fluid ounces or about 3.785 liters (3,785 ml), while in the UK, it is slightly larger at 160 fluid ounces or about 4.546 liters (4,546 ml).
How to convert ounces to gallons
There are 128 fluid oz in a gallon. Whether you want to know how many ounces are in a half gallon, or the number of oz per 1/4 gallon, in the following table you will find answer to all your questions.
Ounces to quarts conversion chart
| Gallons | Ounces | Quarts | Pints | Cups |
|---|---|---|---|---|
| 1/128 | 1 | 1/32 | 1/16 | 1/8 |
| 1/64 | 2 | 1/16 | 1/8 | 1/4 |
| 1/32 | 4 | 1/8 | 1/4 | 1/2 |
| 1/16 | 8 | 1/4 | 1/2 | 1 |
| 1/8 | 16 | 1/2 | 1 | 2 |
| 1/4 | 32 | 1 | 2 | 4 |
| 1/2 | 64 | 2 | 4 | 8 |
| 3/4 | 96 | 3 | 6 | 12 |
| 1 | 128 | 4 | 8 | 16 |
| 11/8 | 176 | 5 1/2 | 11 | 22 |
| 11/4 | 192 | 6 | 12 | 24 |
| 11/2 | 224 | 7 | 14 | 28 |
| 13/4 | 256 | 8 | 16 | 32 |
| 2 | 256 | 8 | 16 | 32 |
What’s the difference between dry and fluid gallons?
There is an important distinction to make, when addressing the question “How many ounces in a gallon?”. At the beginning of this post, we have learnt that there are 128 ounces in one gallon. But in reality, our ounces to gallon ratio will slightly change, if we are measuring dry ingredients or liquids. Well, finding a recipe that calls for dry gallons is hard, but sometimes it happens. And when it does happen, you should remember that a US dry gallon is 1/8 of a Winchester bushel (2150.42 cubic inches) used for grain.
International measurement systems
According to the US customary system, one gallon in oz is equivalent to 128 fluid ounces. But in the UK, Canada, Australia and New Zealand, there are 160 ounces in a gallon. Let me explain why this is happens. If you recall from our calculation of how many ounces in a pint and how many ounces in a quart, there are differences between US system and imperial system. British ounces, pints and gallons are larger than in the US.
Having said that, to convert ounces to gallons we should always consider which country we live in. Here’s a quick summary for you.
- 1 US gallon = 128 fluid ounces
- 1 British gallon = 160 fluid ounces
No, 1 gallon is equal to 128 fluid ounces. 64 oz in gallons is equal to half a gallon.
There are 16 8 oz glasses of water in a gallon of water. Knowing that a gallon of water contains 128 fluid ounces, we just need to multiple 8 oz times 16 glasses. The result is 128 oz.
The amount of water in a bottle can vary based on its size. The three most common bottle sizes are 16.9 oz, 20 oz, and 33.8 oz. Knowing that there are 128 ounces per gallon, a 16.9-ounce bottle holds about 0.13 gallons, a 20-ounce bottle holds about 0.16 gallons, and a 33.8-ounce bottle holds about 0.26 gallons.
To determine how many hydro flasks in one gallon, you must first know the Hydro Flask size. If you have an 18-oz Hydro Flask, you would need about 7.11 of them to make a gallon. For a 32-ounce Hydro Flask, you would need 4 to make a gallon. For a 40-ounce Hydro Flask, you would need 3.2 of them.
There are 64 oz in a half gallon of ice cream. When measuring ice cream, it should be considered as a fluid.
