A US liquid gallon is exactly 3.785411784 liters.
Gallons to Liters Converter — gal to L
Convert Gallon (gal) to Liter (L) using the exact conversion factor (1 gallon = 3.785411784 liter). See the formula, worked examples, conversion table, unit comparison, history, and common uses.
Gallons to Liters converter
Converter
Cooking Converter
Convert cooking volume and mass units used in recipes and nutrition workflows.
Context values
Some unit families need one extra value for a physically accurate result.
A liter is one cubic decimeter.
Result = input x 0.003785411784 / 0.001.
Volume units are compatible.
Reserved above the conversion cards and below the converter.
About Converting Gallons to Liters
Gallon and Liter both show up in recipes, and converting between them matters whenever a recipe from one country's cookbook needs to be followed with another country's measuring tools. Gallon is typically associated with united States (fuel, beverage, and liquid measurement), while Liter is typically associated with standard volume unit for liquids worldwide, including in the US for beverages and fuel labeling in some contexts.
Formula
liters = gallons × 3.785411784
This factor comes from each unit's defined relationship to the category's base unit: 1 gallon equals 0.003785411784 base units, and 1 liter equals 0.001 base units, so dividing one by the other gives the direct gallon-to-liter factor of 3.785411784.
Simple example
1 gal × 3.785411784 = 3.785411784 L
1 gallon = 3.785411784 liters.
Real-world example
2 gal × 3.785411784 = 7.570823568 L
2 gallons = 7.570823568 liters.
Conversion table
| Gallon (gal) | Liter (L) |
|---|---|
| 0.25 gal | 0.946352946 L |
| 0.5 gal | 1.892705892 L |
| 1 gal | 3.785411784 L |
| 2 gal | 7.570823568 L |
| 4 gal | 15.14164714 L |
| 8 gal | 30.28329427 L |
Reverse conversion: Liter to Gallon
3.785411784 L × 0.2641720524 = 1 gal
3.785411784 liters = 1 gallon.
gallons = liters × 0.264172052358
For a page dedicated to this direction, see Liter to Gallon.
Gallon vs. Liter
| Aspect | Gallon | Liter |
|---|---|---|
| Family | US customary unit | Non-SI metric unit accepted for use with SI |
| Typical use | Fuel pump and vehicle fuel-economy measurement in the US | Beverage, fuel, and liquid product packaging worldwide |
| Where it's used | United States (fuel, beverage, and liquid measurement) | Standard volume unit for liquids worldwide, including in the US for beverages and fuel labeling in some contexts |
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 Liter
Liter (L) measures volume. A liter is defined as exactly one cubic decimeter (0.001 cubic meters). It is classified as a Non-SI metric unit accepted for use with SI.
Where it's used: Standard volume unit for liquids worldwide, including in the US for beverages and fuel labeling in some contexts
Uses of the Liter today
- Beverage, fuel, and liquid product packaging worldwide
- Cooking and recipe measurement in metric countries
- Laboratory and scientific volume measurement
History of the Liter
The liter was introduced with the French metric system in 1795, originally defined as the volume of one kilogram of pure water at its freezing point — tying volume, mass, and the meter together.
Between 1901 and 1964, the liter was briefly redefined as the volume of exactly one kilogram of water at its maximum density (about 4 °C), which made it very slightly larger than a cubic decimeter. It was redefined back to exactly one cubic decimeter in 1964, the definition still used today.
Historical origin. Liter 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.
Liter — sources
- BIPM SI Brochure — Non-SI units accepted for use with SI — Current cubic-decimeter definition of the liter.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many liters are in 1 gallon?
1 gallon equals 3.785411784 liters, using the exact defined conversion factor rather than an estimate.
How do I convert gallon to liter?
Multiply the gallon value by 3.785411784. The converter above does this instantly to whatever precision you set.
How do I convert liter back to gallon?
Use the reverse factor: 1 liter equals 0.2641720524 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 liter?
Liter (L) measures volume. A liter is defined as exactly one cubic decimeter (0.001 cubic meters). It is classified as a Non-SI metric unit accepted for use with SI.
Is the gallon to liter conversion exact?
Yes. A liter is defined as exactly one cubic decimeter (0.001 cubic meters). 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)