Gallons to Litres Converter (gal to L)

How to use this calculator: gallons to liters

1. 1Enter the value measured in gallon (us) (gal).
2. 2Confirm the direction is Gallon (US) (gal) to Litre (L); reversing the units changes the factor or offset.
3. 3Apply L = gal × 3.78541. The live converter performs this substitution as you type.
4. 4Read the answer in L and keep only justified precision.

Conversion formula

US gallons convert to litres by multiplying by 3.785411784. A 15-gallon fuel tank holds about 56.8 litres.

The units measure the same quantity at different scales: 1 gal = 3.78541 L, and 1 L = 0.26417218 gal.

Worked conversion example: Gallons to Litres

1. Given: 10 gal
2. Substitute: L = 10 × 3.78541 = 37.8541
3. Result: 10 gal = 37.8541 L

Accuracy checklist

The converter keeps extra precision internally. Report only the precision supported by the original measurement and follow the required rounding rule.

Direction check: a smaller unit usually gives a larger number; temperature is an exception.

Unit definitions and SI traceability: NIST Office of Weights and Measures — SI Units.