Formula to convert 20.5 liters to gallons is to multiply 20.5 by 0.264172 (this is the value for 1 liter to gallon).
Convert 20.5 Liters to Gallons results
20.5 x 0.264172052 = 5.4155270742
20.5 l = 5.42 gal
To conclude the answer for 20.5 liters is five point forty two gallons