How to convert US gallons to litres
One US gallon equals 3.7854 litres, so multiply the number of US gallons by 3.7854:
L = US gal × 3.7854
US gal = L ÷ 3.7854 (1 L = 0.264172 US gal)
Example: 5 US gal → 5 × 3.7854 = 18.9271 L.
Going the other way, divide by 3.7854, or multiply by 0.264172; the litres to US gallons converter does it for you.
Everyday values
| US gallons | Litres | For example |
|---|---|---|
| 1 US gal | 3.7854 L | a gallon of milk |
| 5 US gal | 18.9271 L | a large water bottle for dispensers |
| 13 US gal | 49.2104 L | a typical US car fuel tank, roughly |
| 55 US gal | 208.198 L | an oil drum |
When you need this conversion
Fuel prices in the US are per gallon, in most other countries per litre. To compare, divide the price per gallon by 3.785: 3.50 per gallon is 0.92 per litre. For fuel consumption, see the fuel economy calculator.
US gallon to litre conversion table
| US gal | L | US gal | L |
|---|---|---|---|
| 1 US gal | 3.7854 L | 16 US gal | 60.5666 L |
| 2 US gal | 7.5708 L | 17 US gal | 64.352 L |
| 3 US gal | 11.3562 L | 18 US gal | 68.1374 L |
| 4 US gal | 15.1416 L | 19 US gal | 71.9228 L |
| 5 US gal | 18.9271 L | 20 US gal | 75.7082 L |
| 6 US gal | 22.7125 L | 21 US gal | 79.4936 L |
| 7 US gal | 26.4979 L | 22 US gal | 83.2791 L |
| 8 US gal | 30.2833 L | 23 US gal | 87.0645 L |
| 9 US gal | 34.0687 L | 24 US gal | 90.8499 L |
| 10 US gal | 37.8541 L | 25 US gal | 94.6353 L |
| 11 US gal | 41.6395 L | 26 US gal | 98.4207 L |
| 12 US gal | 45.4249 L | 27 US gal | 102.206 L |
| 13 US gal | 49.2104 L | 28 US gal | 105.992 L |
| 14 US gal | 52.9958 L | 29 US gal | 109.777 L |
| 15 US gal | 56.7812 L | 30 US gal | 113.562 L |
About the units
- US gallon (US gal): 231 cubic inches, exactly 3.785411784 litres.
- Litre (L): one cubic decimetre (1,000 cm³).
Both are units of volume. The conversion factor comes from the exact definitions above, so the calculator is exact; results are only rounded for display (up to six significant digits).
Frequently asked questions
How many litres are in one US gallon?
One US gallon is 3.7854 litres. One litre is 0.264172 US gallons.
How do I convert US gallons to litres?
Multiply the value in US gallons by 3.7854. To go back, divide by 3.7854.
What is 5 US gal in litres?
5 US gal = 18.9271 L.
What is 13 US gal in litres?
13 US gal = 49.2104 L.
Sources
- NIST Special Publication 811 (2008), Guide for the Use of the International System of Units (SI), Appendix B: conversion factors.
- NIST Handbook 44 (2024), Appendix C: General tables of units of measurement.
Last reviewed 5 October 2026. Results are estimates; see our disclaimer.