Instant Unit Conversion
Convert Gallons (US) to Liters (gal to L)
Exact formula, conversion factors, live calculator, and reference charts for gallons (us) to liters.
Method reviewed:Exact defined factors — international yard and pound (1959), US customary gallon and cup, SI — the values NIST SP 811 lists · reviewed September 2026
Direct AnswerFormula: L = gal × 3.785411784
1 US gallon is equal to exactly 3.785411784 liters. To convert US gallons to liters, multiply by 3.785411784.
Live Gallons (US) to Liters Calculator
Formula:
L = gal × 3.785411784Open full volume converter →Gallons (US) to Liters Conversion Table
Quick reference conversion chart from 1 to 100 gallons (us).
| Gallons (US) (gal) | Liters (L) | Mathematical Formula |
|---|---|---|
| 1 gal | 3.7854 L | 1 × 3.78541 |
| 2 gal | 7.5708 L | 2 × 3.78541 |
| 5 gal | 18.9271 L | 5 × 3.78541 |
| 10 gal | 37.8541 L | 10 × 3.78541 |
| 15 gal | 56.7812 L | 15 × 3.78541 |
| 20 gal | 75.7082 L | 20 × 3.78541 |
| 25 gal | 94.6353 L | 25 × 3.78541 |
| 50 gal | 189.2706 L | 50 × 3.78541 |
| 75 gal | 283.9059 L | 75 × 3.78541 |
| 100 gal | 378.5412 L | 100 × 3.78541 |
Frequently Asked Questions
How many liters is 5 gallons?
5 US gallons is 18.93 liters — the size of a typical office water cooler bottle.
What about the imperial gallon?
An imperial gallon is 4.54609 L. If the figure came from a UK source, use that instead: the two differ by about a fifth.
How many US gallons in a barrel of oil?
42 US gallons, which is 158.99 liters.