Ans

Unit converter

Imperial gallons to litres.

Convert gal (imp) to L and L to gal (imp). Type in either box and the other follows. UK fuel economy is quoted per imperial gallon even though fuel is sold by the litre.

gal (imp) → LExact definition
—
Imperial gallons to litres — common values, to 6 significant figures.
gal (imp)L
1 gal (imp)4.54609 L
2 gal (imp)9.09218 L
3 gal (imp)13.6383 L
5 gal (imp)22.7304 L
8 gal (imp)36.3687 L
10 gal (imp)45.4609 L
12 gal (imp)54.5531 L
15 gal (imp)68.1914 L
20 gal (imp)90.9218 L
1 gal (imp)=4.54609 L 1 L=0.2199692483 gal (imp)

Definitions

  • The imperial gallon is exactly 4.546 09 litres, about a fifth larger than the US gallon's 3.785 41 litres.
  • The litre is a thousand cubic centimetres — a cube 10 cm on each side. It is accepted for use with SI but is not itself an SI unit.
  • This conversion is exact by definition. 1 gal (imp) = 4.54609 L.
  • US and imperial units of the same name are different sizes. A US pint is 473 mL; an imperial pint is 568 mL. Every unit below says which system it belongs to.

How it works

One direction multiplies and the other divides by the same number, so nothing is lost by going back and forth.

The value passes through m³, the unit every other volume & capacity unit on the site is defined against, rather than a number written into this page on its own. That is why the figure here, the figure in the table above and the general volume & capacity converter always agree.

Display precision sets a maximum number of significant figures and trims trailing zeroes, so it changes what you see and never what was calculated. The editable box always holds a plain number at full working precision, so you can carry on from either side.

Common questions this answers: how many litres in a gallon (imperial) (4.54609), how many imperial gallons in a litre (0.219969), and what 10 gal (imp) is in litres (45.4609 L).

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