There are three types of gallons dry gallon, imperial gallon and US customary fluid. There are few accepted sizes of cups such as imperial cup, US cup, Canadian cup and metric cup. So depending upon the sizes of gallons and cups used, the answer to this question may differ. The imperial gallons are no longer used today and are replaced by metric gallons. 1 US liquid gallon is equal to 16 US cups.
Gallon:
The gallon is a unit of measurement for (liquid) volume. Its symbol is “gal’. A US liquid gallon measures 3.785 liters, while the imperial (UK) gallon measures 4.546 litres. The imperial gallon is 20% larger than the US gallon.
Gallons in a Cups conversion table
Given below is a reference table of conversions to help you know how many cups are there in a gallon. This chart assumes you are either using the US fluid gallon and cup or the UK gallon and imperial cup.
Liquid GALLONS  CUPS  GALLONS  CUPS 

1  16  11  176 
2  32  12  192 
3  48  13  208 
4  64  14  224 
5  80  15  240 
6  96  16  256 
7  112  17  272 
8  128  18  288 
9  144  19  304 
10  160  20  320 
The Imperial Gallon
The UK or imperial gallon is a unit of measurement exactly 4.54609 liters or 277.42 cubic inches. It is mostly common in the Commonwealth countries and some Caribbean states. The imperial gallon was originally based on 10 pounds which translates to 4.54kg of water at 17 °C. The imperial fluid ounce weighs about 1⁄160 of the imperial gallon. An imperial gallon is divided into four quarts, in which each quart is consisting of two pints and each pint consists of 20 imperial fluid ounces.
US Liquid Gallon
One US gallon is determined as 3.7854 liters or 231 cubic inches. At 62°F (17°C), a US liquid gallon of water is equal to 3.78 kilograms or 8.34 pounds. It is 16.6% lighter as compared to the imperial gallon. However same like the imperial gallon, a US gallon is divided into four quarts, each quart is divided into two pints, and each pint contains 16 United State fluid ounces. Therefore it takes 128 US fluid ounces to fill a US liquid gallon. It is common to specify the temperature at which the material will occupy or weigh a particular volume. This is done to overcome the change in volume or mass that results from the change in temperature. In the US the weight of petroleum and alcoholic products are defined as 60°F (16°C).
US Dry Gallon
The US dry gallon is equal to an eight of the Winchester bushel, 4.4.5 liters or 268.8025 cubic inches.
1 Gallon [Fluid, US] = 3.7854118 Liters
1 Gallon [Dry, US] = 4.4048838 Liters
1 Gallon [UK] = 4.54609 Liters
Gallon Measurements
US liquid gallon = 3.785411784 L
US dry gallon = 4.405 L (rarely used)
Imperial (UK) gallon = 4.54609 L
Cup measurements
When it comes to the cup, there are different sizes of the cups. The three main ones to be aware of are mentioned:
US cup = 236.588 mL
Imperial cup (pre1970s UK recipes) = 284.131 mL
Metric cup (used in UK and Commonwealth countries) = 250 mL
US Gallons to cups:
1 Gallon (Dry US) = 18.618355 Cups (US)
1 Gallon (US Fluid) = 16 cups (US)
UK Gallons to cups:
1 Gallon (UK imperial) = 18.18436 Cups (metric)
1 Gallon (UK imperial) = 16 Cups (imperial)
Gallons  Cups 

1 US fluid gallon  16 US cups 
1 US dry gallon  18.6 US cups 
1 Imperial gallon  18.18 metric cups 
1 gallon of water  16 cups 
1 gallon of milk  16 cups 
1 gallon of coffee  20 cups of coffee beans 
½ gallon of water  8 cups 
½ gallon of milk  8 cups 
½ gallon of coffee  8 cups 
How to convert gallons to litres:
Liter:
A liter (symbol L) is a unit of volume that is accepted for use with the International System of Units (SI) but technically it is not an SI unit. One liter is equivalent to 1 cubic decimeter (dm3), 1,000 cubic centimeters (cm3), or 1/1,000 cubic meters (m3). The unit liter is used to measure many liquid volumes as well as to label containers containing liquids.
1 gallon is equal to 3.5785 litres. To convert gallons to litres multiply the given gallon value by 3.75785.
For example; how many litres in 7 gallons multiply 7 by 3.5785 that makes 25.04 litres in 7 gallons.
1 L = 0.2641720524 gal (US)
1 gal (US) = 3.785411784 L.
Example: convert 14 L, to gal (US):
14 L = 14 × 0.2641720524 gal (US) = 3.6984087 gal (US)
How Many Milliliters in a gallon?
A milliliter (symbol mL) is a unit of volume that is accepted for use in the international system of units (SI). One milliliter is equivalent to 1 cubic centimeter (cm3), 1/1,000,000 cubic meters (m3), or 1/1000 liters.
1 gal (US) = 3785.411784 mL
1 mL = 0.0002641721 gal (US)
Example: convert 14 gal (US) to mL:
14 gal (US) = 14 × 3785.411784 mL = 52995.676 mL
What is a quart?
A fluid quart is a unit of liquid volume and is equivalent to a quarter gallon or two pints. The US quart (946.35mL) is quite smaller than the UK quart (1136.52mL). That said if you are using kitchen measurements from the same country, conversions are straight forward:
US quarts to cups

1 Quart (Dry US) = 4.6546 Cups (US)

1 Quart (US fluid) = 4 cups (US)
UK quarts to cups
 1 Quart (UK, fluid) = 4 Cups (UK, imperial)
If using the metric cup

1 US Quart (fluid) = 3.7854 metric cups

1 UK Quart = 4.54 metric cups
Here are the common units of capacity from smallest to largest:

Fluid ounces

Cups

Pints

Quarts

Gallons
For kids to make them learn easily a teacher made a gallon man by the following method: Gallon Man is very easy to make. You just need 5 sheets of differently colored construction paper.
The gallon is a full sheet of paper.
There are 4 quarts in one gallon, so for the quarts, fold the paper in half twice and write Quart on each side.
The quarts are divided into pints. There are 2 pints in each quart (8 pints in a gallon) so for this sheet of paper fold it into 8 squares.
The pints are divided into cups. There are 2 cups in a pint (16 cups in a gallon) so the next sheet needs to be folded into 16 squares.
The final piece of paper is to make Gallon Man’s head. Draw a happy face on it. Glue it all together and you have Gallon Man ready.
Summary:
Here with the help of the above article we have learned how many cups are present in a gallon? The answer is simple there are 1 US liquid gallon is equal to 16 US cups.
Frequently Asked Questions:
How many cups ae in half a gallon?
A gallon is 128 Ounces so 1/2 gallon is 64 Ounces.
A cup is 8 Ounces. So there are 8 cups to a half gallon.
How many quarts in a gallon?
A gallon is equal to 4 quarts
How many cups are in a gallon?
There are 16 cups in a gallon
How many cups in a pint?
There are 2 cups in a pint
HOW MANY CUPS IN A HALF GALLON?
There are 8 cups in a half gallon.
HOW MANY OUNCES IN A GALLON?
There are 128 ounces in a gallon.
Is a gallon of water in a day too much?
Drinking a gallon (3.8 liters) of water per day is unnecessary — unless your body requires that much water for proper hydration. Drinking a gallon of water per day may work for some people while could be harmful for others. It’s rare but drinking too much water too fast can cause sodium levels in your blood to drop too low causing a dangerous condition called hyponatremia.
How many cups in a half gallon of milk?
Since we currently learned that there are 16 cups in a gallon, a halfgallon milk would have 8 cups in it.
1 HALF GALLON OF MILK = 8 CUPS
How many 32 ounces cups make a gallon?
In this part we will follow a similar calculation for the 8ounce cups in a gallon. Since we learned that there are 128 ounces in a gallon, we will partition 128 to 32.
We will get the estimated value of 4. For this situation 32 ounce cups is comparable to a large portion of a gallon. Moreover, on the grounds that we likewise learned that 32 ounces is equivalent to one quart at that point there are additionally four quarts in a single gallon.
1 GALLON = 4 32OUNCE CUPS
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