To convert US gallons to liters, multiply by 3.78541. So 1 gal = 3.785 L, 5 gal = 18.93 L, and 10 gal = 37.85 L. The UK imperial gallon is larger (4.546 L) - this converter uses US gallons.
- Formula: L = gal × 3.78541. Quick mental anchor: 1 gallon is about 3.8 liters.
- 5 gal = 18.93 L (water cooler). 10 gal = 37.85 L. 50 gal = 189.3 L.
- US gallon = 3.785 L. UK imperial gallon = 4.546 L - a 20% difference.
- Reverse: gal = L × 0.264172.
How to use our gal to L converter
Type any gallon value in the gal field and the liter result appears instantly. You can also type in the liter field to convert back to gallons - both directions work without pressing a button.
How do you convert gallons to liters?
Multiply the number of US gallons by 3.78541. The US liquid gallon is defined exactly as 231 cubic inches, which equals 3.785411784 liters (rounded to 3.78541 for practical use).
$$\text{L} = \text{gal} \times 3.78541$$
Worked examples: 1 gal = 3.785 L. 2 gal = 7.571 L. 5 gal = 18.927 L. 10 gal = 37.854 L. 20 gal = 75.708 L. 50 gal = 189.271 L. 100 gal = 378.541 L.
How do you convert liters to gallons?
Multiply liters by 0.264172. See the dedicated liters to gallons converter for a liters-first reference table.
$$\text{gal} = \text{L} \times 0.264172$$
Worked examples: 10 L = 2.642 gal. 20 L = 5.283 gal. 40 L = 10.567 gal. 100 L = 26.417 gal.
Gallons to liters reference table
Standard US gallon values converted to liters, with practical reference contexts:
| Gallons (gal) | Liters (L) | Context |
|---|---|---|
| 0.5 gal | 1.893 L | Half gallon |
| 1 gal | 3.785 L | Standard gallon container |
| 2 gal | 7.571 L | Large water pitcher / 2-gal jug |
| 5 gal | 18.927 L | Water cooler jug |
| 10 gal | 37.854 L | Small aquarium |
| 15 gal | 56.781 L | Medium fuel tank |
| 20 gal | 75.708 L | Larger fuel tank |
| 50 gal | 189.271 L | Barrel / large tank |
| 100 gal | 378.541 L | Large cistern |
FAQs about US gallons to liters conversion
How many liters is 1 gallon?
1 US gallon equals 3.78541 liters. The UK imperial gallon is larger at 4.546 liters. This converter uses US liquid gallons - the standard in North America.
How many liters is 5 gallons?
5 US gallons equals 18.927 liters. 5 × 3.78541 = 18.927 L. A standard water cooler jug is 5 gallons (18.9 L).
How many liters is 10 gallons?
10 US gallons equals 37.854 liters. 10 × 3.78541 = 37.85 L. A 10-gallon aquarium holds about 38 liters of water.
How many gallons is 10 liters?
10 liters equals 2.642 US gallons. 10 × 0.264172 = 2.64 gal. A 10-liter gas can holds about 2.6 gallons of fuel.