Calculate fuel economy (MPG, km/L, L/100km) and convert between different fuel efficiency units.
| Vehicle | MPG | km/L | L/100km |
|---|---|---|---|
| Compact car | 35 | 14.9 | 6.7 |
| Midsize sedan | 28 | 11.9 | 8.4 |
| Full-size sedan | 22 | 9.4 | 10.7 |
| Compact SUV | 28 | 11.9 | 8.4 |
| Midsize SUV | 23 | 9.8 | 10.2 |
| Full-size SUV | 17 | 7.2 | 13.8 |
| Pickup (V6) | 22 | 9.4 | 10.7 |
| Pickup (V8) | 18 | 7.7 | 13.1 |
| Minivan | 24 | 10.2 | 9.8 |
| Hybrid | 52 | 22.1 | 4.5 |
| Electric (MPGe) | 120 | 51.0 | 2.0 |
A driver in the UK who reports 40 mpg and a driver in the US who reports 33 mpg can be describing the same car. The mile is the same; the gallon is not. An imperial gallon is 4.546 litres and a US gallon is 3.785, a ratio of 1.20095. This calculator works out fuel economy from distance and fuel used, shows it in four units, and includes a converter for figures you read elsewhere.
The page computes US mpg = miles ÷ US gallons and derives the rest from it. UK mpg = US mpg × 1.20095. Kilometres per litre = US mpg × 0.425144. Litres per 100 km = 235.215 ÷ US mpg.
The converter runs those backwards: UK mpg ÷ 1.20095 gives US mpg, km/L ÷ 0.425144 gives US mpg, and L/100 km becomes 235.215 ÷ the value. Miles per gallon is distance per fuel and L/100 km is fuel per distance, so they are reciprocal and the scale is not linear. Going from 25 to 30 mpg cuts fuel use per 100 miles from 4.00 to 3.33 gallons, a saving of 0.67. Going from 10 to 15 mpg cuts it from 10.00 to 6.67 gallons, a saving of 3.33.
Worked example: 412 miles on 11.8 US gallons. 412 ÷ 11.8 = 34.92 US mpg. UK mpg is 34.92 × 1.20095 = 41.93. Kilometres per litre is 34.92 × 0.425144 = 14.84. Litres per 100 km is 235.215 ÷ 34.92 = 6.74. Everything is displayed to two decimals, and a zero or negative result is shown as a dash.
The calculator assumes US gallons. With imperial gallons the figure labeled US MPG is really UK MPG: 412 miles on 11.8 imperial gallons is 34.92 UK mpg, or 29.07 US mpg. For litres, convert to gallons first by dividing by 3.78541.
Both are about 29.4 US mpg, since 12.5 km/L is the same as 8 L/100 km. In UK miles per gallon that is about 35.3.
Pump shut-off varies, and partial fills hide fuel. Compare over several tanks using total miles ÷ total gallons, not the average of individual mpg figures, which gives short tanks too much weight.
No. The class table lists electric cars in MPGe, which compares energy using 33.7 kWh per gallon of gasoline equivalent, but this page does not calculate it.
A distance of zero or less, or a zero fuel amount, gives no valid result. The page needs positive miles and a positive volume of fuel.