How to Calculate Gallons to Liters
What is Gallons to Liters?
A gallons to litres converter converts US or imperial gallon measurements to litres, the standard metric unit of volume used worldwide.
Formula
L = gal_US × 3.78541; L = gal_UK × 4.54609
- gal_US
- US gallons (US gal) — Imperial-derived unit used in US
- gal_UK
- UK gallons (UK gal) — Imperial gallon standard in UK and Commonwealth
- L
- Litres (L) — Metric volume unit
Step-by-Step Guide
- 11 US Gallon = 3.78541 litres
- 21 Imperial Gallon = 4.54609 litres
- 3US Gallons × 3.78541 = Litres
- 4Imperial Gallons × 4.54609 = Litres
Worked Examples
Input
1 US gallon
Result
3.785 litres
Input
5 US gallons
Result
18.927 litres
Input
10 imperial gallons
Result
45.461 litres
Frequently Asked Questions
What is a gallon?
A gallon is a unit of volume. The US gallon = 3.785 litres; the UK (imperial) gallon = 4.546 litres. Always confirm which definition applies.
How do I know if I need US or UK gallons?
US gallons are used in the United States, Liberia, and Myanmar. UK gallons are used in the UK and most Commonwealth nations. Check the source — fuel pumps and recipes will specify.
Can I estimate the conversion quickly?
Quick rule: multiply US gallons by 3.8 for litres. UK gallons are larger — multiply by 4.5. These approximations work well for rough calculations.
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