Liters to Gallons Converter
Convert litres to US or UK gallons, and gallons back to litres.
Formula and sources updated · Data sources · 1View algorithm, constants and default inputs (JSON)
1 US gal = 3.785411784 L
About this calculator
US and UK gallons are not the same unit — the imperial gallon is about 20% larger. Getting them confused is a common and sometimes expensive error when buying fuel or paint.
Worked example
calculated with the default values below
Value 50 · Direction ⇄ · Decimal places 4 · From Litres (L) · To US gallons Result 13.2086 · Litres 50.0000 L · US gallons 13.2086 gal · UK gallons 10.9985 gal
Method and assumptions
1 US gallon = 3.785411784 L; 1 imperial gallon = 4.54609 L. US customary and imperial liquid measures differ. This is volume, not ingredient mass; no density conversion is performed.
Data sources
Disclaimer
These calculators give general conversion results. Rounding and the precision of the value you enter both affect the output, so treat displayed decimals as indicative rather than exact.
Implementation source
This record describes the implementation used by this page. It is not independent validation. External references, when available, support only the stated formula or definition; estimates and custom rules retain their own assumptions.
Formula and variables
L = gal_US × 3.785411784; gal_US = L ÷ 3.785411784; gal_UK = L ÷ 4.54609
- L
- litres
- gal_US
- US gallons
- gal_UK
- UK (imperial) gallons
- value
- entered amount
Direction selects US gallons → litres, litres → US gallons, or litres → UK gallons.
Frequently asked questions
Why does the imperial gallon give a smaller number than the US gallon?
The tool divides litres by different constants for the two systems: 3.785411784 for the US gallon and 4.54609 for the imperial gallon. Because the imperial gallon is about 20 percent larger, 50 litres becomes 13.21 US gallons but only 11.00 UK gallons, a 2.21 gallon gap. The Direction select picks which constant is used, so the same 50 litres always lands two gallons apart across the two outputs.
Which inputs and limits apply to Liters to Gallons Converter?
Use the units shown beside each field. These are form limits, not recommended settings. Value: 0–1,000,000,000,000 1 US gallon = 3.785411784 L; 1 imperial gallon = 4.54609 L. US customary and imperial liquid measures differ. This is volume, not ingredient mass; no density conversion is performed.
What is a complete worked example for Value = 50; Direction = ⇄?
Inputs: Value = 50; Direction = ⇄; Decimal places = 4; From = Litres (L); To = US gallons. Calculation: L = gal_US × 3.785411784; gal_US = L ÷ 3.785411784; gal_UK = L ÷ 4.54609. Results: Result = 13.2086 US gal; Litres = 50.0000 L; UK gallons = 10.9985 gal.