How to convert US gallons to liters
Every US gallon is 3.7854 liters, so the conversion is a single multiplication:
Worked example: 25 gal → 25 × 3.78541 = 94.6353 L.
Quick mental estimate: Multiply by 3.8: 25 × 3.8 ≈ 95 L (exact: 94.6353).
US gallons to liters conversion table
| US gallons (gal) | Liters (L) |
|---|---|
| 1 gal | 3.7854 L |
| 2 gal | 7.5708 L |
| 3 gal | 11.3562 L |
| 5 gal | 18.9271 L |
| 10 gal | 37.8541 L |
| 15 gal | 56.7812 L |
| 20 gal | 75.7082 L |
| 25 gal | 94.6353 L |
| 50 gal | 189.27 L |
| 75 gal | 283.91 L |
| 100 gal | 378.54 L |
| 200 gal | 757.08 L |
| 250 gal | 946.35 L |
| 500 gal | 1,892.71 L |
| 1,000 gal | 3,785.41 L |
Values rounded to four decimals. For a value that is not in the table, use the converter above — it accepts decimals and negative numbers.
When you need this conversion
- Recipes, especially between American cup-based measures and metric millilitres.
- Fuel consumption and tank capacities, quoted in gallons in the United States and litres almost everywhere else.
- Paint, chemicals and garden products, sold in different container sizes by region.
Getting it right
The US gallon (3.785 L) and the UK imperial gallon (4.546 L) are different units sharing a name. A figure taken from a British source is about 20 % larger than the same number of US gallons — always check which one is meant.
Sanity-check the direction of the result before you use it. One US gallon is 3.7854 liters, so converting US gallons to liters should make the number larger. If it moved the other way, the conversion was applied backwards — the reverse converter is one click away.
About the units
US gallon (gal)
The US gallon is exactly 3.785411784 liters. Fuel, milk and paint are sold by the gallon in the United States. The UK imperial gallon is larger, at 4.546 liters, so check which one a figure refers to.
Liter (L)
The liter is one cubic decimeter, or 1 000 milliliters. Drinks, fuel, engine displacement and household containers are measured in liters.
Frequently asked questions
How many liters are in 1 US gallon?
1 US gallon equals 3.7854 liters. To convert any value, multiply the number of US gallons by 3.78541.
How do I convert US gallons to liters in my head?
Multiply by 3.8: 25 × 3.8 ≈ 95 L (exact: 94.6353).
Is the gal to L conversion exact?
1 US gallon is exactly 3.785411784 L; 3.78541 is that value rounded.
How do I convert US gallons to liters in Excel or Google Sheets?
Put the value in A1 and use =A1*3.78541. Both Excel and Google Sheets also have a built-in function, =CONVERT(A1,"gal","l"), which avoids typing the factor by hand.
How many decimal places should I keep?
For everyday use two decimals are plenty. Keep four if the result feeds another calculation, and round only at the very end — rounding intermediate steps is the most common reason a result comes out slightly wrong.