gallons to liters formula
To convert US gallons to liters, multiply the number of US gallons by 3.785411784. In symbols: L = gal × 3.785411784.
One US gallon equals 3.785411784 liters, and one liter equals 0.264172052358 US gallons. The US gallon is exactly 231 cubic inches, and with the inch fixed at 2.54 cm this makes 1 gallon exactly 3.785411784 L.
Worked example
Suppose you have 12 US gallons and need the answer in liters.
- Write the formula: L = gal × 3.785411784.
- Put in the number: 12 × 3.785411784 = 45.42494141.
- Round to suit the job. 45.42 L is accurate enough for most everyday uses.
So 12 gal is 45.42494141 L. To check, convert back: 45.42494141 L is 12 gal.
Common US gallons to liters values
| US gallons (gal) | liters (L) |
|---|---|
| 1 | 3.785411784 |
| 2 | 7.570823568 |
| 5 | 18.92705892 |
| 10 | 37.85411784 |
| 20 | 75.70823568 |
| 50 | 189.2705892 |
| 100 | 378.5411784 |
Reference points
Some familiar amounts in US gallons, converted to liters:
- 1 gal, a milk jug: 3.78541 L
- 5 gal, a typical bucket of paint: 18.9271 L
- 12 gal, a mid-size car tank: 45.4249 L
- 55 gal, a standard oil drum: 208.198 L
Where you will use it
US gas pumps, paint cans, milk jugs and fish tanks are labeled in gallons. Anyone driving a rental car in the US or importing a car needs the figure in liters.
Quick mental math
Multiply by 4 and subtract 5 percent. 12 gallons gives 48 less 2.4, about 45.6 L against the exact 45.42. Rule of thumb: multiply by 3.8. For 12 gal this gives 45.6 L against the exact 45.42, an error of 0.39 percent.
Going the other way
Need the reverse? Use the liters to gallons converter. For comparison, 1 L is 0.26417205 gal. To compare every volume unit at once, open the volume converter.
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