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US cups to US gallons Converter

Convert US cups (cup) to US gallons (gal) instantly, or use the conversion table below to look up common values.

1 cup = 0.0625 gal

US cups to US gallons conversion table

US cups (cup)US gallons (gal)
10.0625
20.125
30.1875
40.25
50.3125
100.625
251.5625
503.125
1006.25

How to convert US cups to US gallons

1 cup equals 0.0625 gal. Use the converter above for any value, or read the table for common conversions.

gal = cup × 0.0625 · cup = gal × 16

Multiply a us cups figure by 0.0625 to get us gallons, or divide it by 16 to go the other way.

Worked examples

  • 1 cup= 0.0625 gal
  • 2 cup= 0.125 gal
  • 5 cup= 0.3125 gal
  • 10 cup= 0.625 gal
  • 20 cup= 1.25 gal

What these units are

US cups (cup). A US cup is 236.5882365 milliliters, or 8 US fluid ounces. It is the standard measure in American recipes; metric and Australian cups are 250 milliliters, so a recipe's cup depends on where it was written.

US gallons (gal). A US gallon is 3.785411784 liters, defined as 231 cubic inches. It is the standard liquid and fuel unit in the United States, and is about 20% smaller than an imperial gallon.

US and imperial units are kept separate because they are genuinely different sizes. Confirm which system a source means before trusting a converted figure.

Converting US cups to US gallons in practice

Working in us cups

A US cup is exactly 236.5882365 milliliters, one sixteenth of a US gallon and eight US fluid ounces. It is a recipe measure rather than a general liquid unit.

It appears in American and adapted recipe books, baking charts, measuring cup sets and some packaged food directions. Outside cooking it is rarely a legal or trade unit.

The US cup is exactly eight US fluid ounces, so cup to milliliter conversions are exact at 236.5882365. Results are rounded for display, which can shift the last digit on a return conversion.

The trap is the US legal cup of 240 milliliters used on nutrition labels, and the separate metric cup of 250 milliliters; neither matches this unit. Recipe cups are also level, not heaped.

The US cup belongs with US fluid ounces and pints, while milliliters and liters belong to the metric recipe. A metric jug marked in milliliters will not match a cup measure exactly, so a recipe converted cup by cup accumulates a small error each step.

Reading the result in us gallons

A US gallon is exactly 3.785411784 liters, or 231 cubic inches, and it divides into four quarts, eight pints or 128 US fluid ounces. It is a defined liquid volume and not a unit of mass.

Fuel at filling stations, paint, milk, water and agricultural sprays are sold by the US gallon in the United States and in some export markets. Larger tanks and drums are also rated in gallons.

The site uses the US gallon of exactly 3.785411784 liters; the imperial gallon is exactly 4.54609 liters and is roughly a fifth larger. Display rounding can move the final digit of a gallon to liter conversion taken both ways.

The frequent mistake is applying the imperial gallon to a US figure or the reverse, which misstates fuel or tank volume by around a fifth. A gallon also measures volume, while a gallon of a specific liquid has a mass.

The US gallon belongs with quarts, pints and fluid ounces, while the imperial gallon and the liter sit on other scales. Fuel is sold by the gallon in some markets and by the liter in others, so a consumption figure must be converted first.

Checking a us cups to us gallons conversion

The metric volume units are a clean decimal chain around the liter, so liters to milliliters is a shift of three places and cubic meters to liters is a shift of three the other way. Those pairs a reader can do without a converter.

Every pair that names a US or imperial liquid unit has to go through the definition first, because three of these units differ from a metric unit by amounts too large to round away: a liter is not a quart, a gallon is 3.785411784 liters in the US system and 4.54609 in the imperial one, and a US fluid ounce is not an imperial fluid ounce.

When checking a volume conversion, convert into liters and out again, or measure the container. The mistake that survives every other check is reading a US measure as the imperial unit of the same name, which changes a recipe, a fuel figure or a tank size by about a fifth.

Tanzania reference points

Real quantities, converted into the units on this page.

  • The 20-litre bucket or canister used to carry water in Tanzania

    20 L = 84.535057 cup = 5.283441 gal

    WaterAid puts the minimum daily water need per person at 20 litres, so one container is roughly one person's daily requirement.

    Source: IPS News — water access in Tanzania, citing WaterAid · verified 2026-09-14

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