Convert US Gallon to Cup (gal (US)cup)

The US gallon is the standard unit for fuel, milk, and beverages across the United States.

15.772549
1 gal (US)15.772549 cupNIST · BIPM accuracy

US Gallon to Cup Conversion Table

10 common values
US GallonCup
1 gal (US)15.772549 cup
2 gal (US)31.545098 cup
5 gal (US)78.862746 cup
10 gal (US)157.72549 cup
20 gal (US)315.45098 cup
50 gal (US)788.62745 cup
100 gal (US)1,577.2549 cup
200 gal (US)3,154.5098 cup
500 gal (US)7,886.2746 cup
1,000 gal (US)15,772.549 cup

How to Convert US Gallon to Cup Manually

Step by Step

Converting US gallons to cups is straightforward: multiply by the conversion factor. Follow these three steps to do it by hand or in your head.

  1. 1
    Take your value in US gallons
    Start with the number of US gallons (gal (US)) you want to convert.
  2. 2
    Multiply by 15.772549
    The conversion factor from gal (US) to cup is 15.772549. Multiply your value by this number.
  3. 3
    Read the result in cups
    The result is your value in cups (cup).
Practical Examples
1 gal (US)
equals
15.772549 cup
5 gal (US)
equals
78.862746 cup
10 gal (US)
equals
157.72549 cup
25 gal (US)
equals
394.31373 cup
100 gal (US)
equals
1,577.2549 cup

Formula

Multiply the value in US gallons by 15.772549. For the reverse direction, multiply by 0.063401.

Forwardcup = gal (US) × 15.772549
Reversegal (US) = cup × 0.063401
Example: 10 gal (US) × 15.772549 = 157.72549 cup

Tips

Use these in everyday conversions
  • 1 US gallon = 3.785 L = 128 US fluid ounces = 4 quarts.
  • Converting mpg (US) to L/100 km: 235.215 / mpg = L/100 km.
  • The US gallon is based on the old English Queen Anne wine gallon (1707).

Common Mistakes

Avoid these
  • Using UK gallons on a US fuel-economy figure — 30 mpg (US) = 36 mpg (UK).
  • Confusing US gallon (3.79 L) with UK gallon (4.55 L) — 20% difference.
  • Using "gallon" without qualifier in cross-Atlantic commerce.

About US Gallon and Cup

What is the US Gallon?

The US liquid gallon equals exactly 3.785411784 liters and is the standard volume unit for fuel, beverages, milk, and household liquids in the United States. Defined as 231 cubic inches, the US gallon descends from the English wine gallon of 1707, which Britain replaced with the larger imperial gallon in 1824 — a divergence that left the United States with a different gallon than the rest of the English-speaking world. American gas stations price gasoline by the gallon (typical fill-up: 12–15 gallons), milk is sold in half-gallons and gallons, and many beverages come in fluid-ounce subdivisions of the gallon. The US gallon relates to the liter (1 gal ≈ 3.785 L), the quart (4 qt = 1 gal), the pint (8 pt = 1 gal), the cup (16 cups = 1 gal), and the imperial gallon (1 imp gal ≈ 1.201 US gal — about 20% larger).

  • US fuel pricing and consumption
  • US paint, oil and cleaning-product packaging
  • US beverage containers (1-gallon jugs of milk)
Real-world examples

US car tank ≈ 15 gallons (57 L). 1 US gallon of milk is a common grocery size (3.79 L). US paint often sold by the gallon.

What is the Cup?

The US cup equals exactly 240 milliliters (a definition standardized for nutrition labeling; the legal volume for cooking is 236.588 mL, derived from 8 US fluid ounces). The cup is the cornerstone of American baking and home cooking, with virtually every US recipe using volume measurements rather than the weight measurements common in European cooking. Standard measuring-cup sets include 1, ½, ⅓, and ¼ cup sizes. The metric cup (used in Australia, New Zealand, and increasingly in international recipes) is exactly 250 mL — slightly larger than the US cup. The cup relates to the gallon (16 cups = 1 gal), the pint (2 cups = 1 pt), the fluid ounce (8 fl oz = 1 cup), the tablespoon (16 tbsp = 1 cup), and the milliliter (1 cup ≈ 237–240 mL). American baking-by-volume is sometimes criticized internationally for its variability compared to gram-based measurements.

  • US cooking and baking recipes
  • Cereal and beverage serving sizes in US nutrition labels
  • Volume estimation when no scale is available
Real-world examples

1 cup of water = 240 g = 240 ml. 1 cup of all-purpose flour weighs about 125 g. A Starbucks Tall is 12 fl oz = 1.5 cups.

Learn About Both Units

🧪 Reference

What is the US Gallon?

Read the unit page →
🧪 Reference

What is the Cup?

Read the unit page →

US Gallon to Cup FAQ

5 questions
How many cups in a us gallon?
One us gallon equals 15.772549 cups.
How do I convert US gallons to cups?
Multiply the us gallon value by 15.772549 to get the equivalent in cups.
What is 100 US gallons in cups?
100 US gallons equals 1,577.2549 cups.
Is a us gallon bigger than a cup?
Yes. 1 us gallon equals 15.772549 cups, so one us gallon is larger.
How to convert US gallons to cups without a calculator?
Multiply by 15.77 for a quick estimate; use a calculator for precise results.

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