A US liquid gallon is exactly 3.785411784 liters.
Gallons to Cups Converter — gal to cup
Convert Gallon (gal) to Cup (cup) using the exact conversion factor (1 gallon = 16 cup). See the formula, worked examples, conversion table, unit comparison, history, and common uses.
Gallons to Cups converter
Converter
Volume Converter
Convert metric, US customary, imperial, cooking, dry, and industrial volume units.
Context values
Some unit families need one extra value for a physically accurate result.
A US customary cup is 236.5882365 milliliters.
Result = input x 0.003785411784 / 0.0002365882365.
Volume uses the cubic meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Gallons to Cups
Gallon and Cup appear side by side at fuel pumps and on beverage labels, since the US measures liquids in gallons while most of the world uses liters. Gallon is typically associated with united States (fuel, beverage, and liquid measurement), while Cup is typically associated with united States (recipes and cooking measurement).
Formula
cups = gallons × 16
This factor comes from each unit's defined relationship to the category's base unit: 1 gallon equals 0.003785411784 base units, and 1 cup equals 0.0002365882365 base units, so dividing one by the other gives the direct gallon-to-cup factor of 16.
Simple example
1 gal × 16 = 16 cup
1 gallon = 16 cups.
Real-world example
10 gal × 16 = 160 cup
10 gallons = 160 cups.
Conversion table
| Gallon (gal) | Cup (cup) |
|---|---|
| 1 gal | 16 cup |
| 5 gal | 80 cup |
| 10 gal | 160 cup |
| 25 gal | 400 cup |
| 50 gal | 800 cup |
| 100 gal | 1,600 cup |
Reverse conversion: Cup to Gallon
16 cup × 0.0625 = 1 gal
16 cups = 1 gallon.
gallons = cups × 0.0625
For a page dedicated to this direction, see Cup to Gallon.
Gallon vs. Cup
| Aspect | Gallon | Cup |
|---|---|---|
| Family | US customary unit | US customary unit (culinary) |
| Typical use | Fuel pump and vehicle fuel-economy measurement in the US | US recipe and cooking measurement |
| Where it's used | United States (fuel, beverage, and liquid measurement) | United States (recipes and cooking measurement) |
Understanding the Gallon
Gallon (gal) measures volume. The US liquid gallon is defined as exactly 231 cubic inches, equal to 3.785411784 liters. It is classified as a US customary unit.
Where it's used: United States (fuel, beverage, and liquid measurement)
US gallon vs. imperial gallon. The US liquid gallon (3.785411784 L) and the British imperial gallon (4.54609 L) are different units with the same name; always confirm which one a source is using.
Uses of the Gallon today
- Fuel pump and vehicle fuel-economy measurement in the US
- Beverage and liquid product packaging in the US
- Cooking and recipe measurement in US customary units
History of the Gallon
The US gallon descends from the English wine gallon of 231 cubic inches, a standard used for measuring wine in medieval and early modern England, which the American colonies inherited and retained even after England moved to a different imperial gallon in 1824.
England's 1824 Weights and Measures Act replaced the old wine gallon with a new imperial gallon (based on 10 pounds of water), but the US kept the older 231-cubic-inch definition — which is why the US gallon (3.785 L) and the imperial gallon (4.546 L) differ by about 20% today.
Historical origin. Gallon was not the invention of a single named person; it developed through the process described above.
Understanding the Cup
Cup (cup) measures volume. The US customary cup used in cooking is defined as exactly 240 milliliters (a rounded culinary standard, not the older 236.588 mL legal cup). It is classified as a US customary unit (culinary).
Where it's used: United States (recipes and cooking measurement)
Cooking cup vs. legal US cup. US recipes commonly round the cup to 240 mL for convenience, while the precise legal US cup (used to derive fluid ounces, pints, etc.) is 236.588 mL — a small but sometimes noticeable difference in precise baking.
Uses of the Cup today
- US recipe and cooking measurement
- Nutrition labeling serving sizes
- Baking, where volume-based flour/sugar measurement is still common in the US
History of the Cup
The cup as a cooking measure grew out of household and community cookbook conventions in 19th-century America, standardizing what had been ad hoc measurements ('a teacup of flour') into a fixed volume.
The US FDA uses a rounded 240 mL 'metric cup' for nutrition labeling purposes, distinct from the slightly smaller legal/customary cup (236.588 mL, exactly 1/16 of a US gallon) used elsewhere.
Historical origin. Cup was not the invention of a single named person; it developed through the process described above.
Gallon — sources
- NIST Handbook 44, Appendix C — General tables of units of measurement, including the US gallon definition.
Cup — sources
- US FDA — Reference Amounts Customarily Consumed — Uses the 240 mL rounded cup for nutrition labeling.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many cups are in 1 gallon?
1 gallon equals 16 cups, using the exact defined conversion factor rather than an estimate.
How do I convert gallon to cup?
Multiply the gallon value by 16. The converter above does this instantly to whatever precision you set.
How do I convert cup back to gallon?
Use the reverse factor: 1 cup equals 0.0625 gallons. You can also use the swap control in the converter above to flip the direction instantly.
What is a gallon?
Gallon (gal) measures volume. The US liquid gallon is defined as exactly 231 cubic inches, equal to 3.785411784 liters. It is classified as a US customary unit.
What is a cup?
Cup (cup) measures volume. The US customary cup used in cooking is defined as exactly 240 milliliters (a rounded culinary standard, not the older 236.588 mL legal cup). It is classified as a US customary unit (culinary).
Is the gallon to cup conversion exact?
Yes. The US customary cup used in cooking is defined as exactly 240 milliliters (a rounded culinary standard, not the older 236.588 mL legal cup). That fixed definition is what the converter above uses, so any rounding you see is a display choice, not a limitation of the math.
What is the difference between us gallon vs. imperial gallon?
The US liquid gallon (3.785411784 L) and the British imperial gallon (4.54609 L) are different units with the same name; always confirm which one a source is using.
Where is the gallon still used today?
United States (fuel, beverage, and liquid measurement)