Formula to convert 4.2 liters to gallons is to multiply 4.2 by 0.264172 (this is the value for 1 liter to gallon).
Convert 4.2 Liters to Gallons results
4.2 x 0.264172052 = 1.10952262008
4.2 l = 1.11 gal
To conclude the answer for 4.2 liters is one point eleven gallons