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Convert MPGe, kWh per 100 miles and more.
Enter one figure in any unit and see all the others. Uses the EPA convention of 33.7 kWh per gallon of gasoline.
Inputs
Starting values are illustrative, not current prices or specifications. Replace each with your own.
Result
Answer
MPGe equals 33.7 divided by kWh per mile, so 100 MPGe is 33.7 kWh per 100 miles, or 2.97 miles per kWh. Lower kWh per 100 miles and higher MPGe both mean a more efficient car.
Worked example
100 MPGe means 33.7 kWh per 100 miles (33.7 ÷ 100 × 100). That is 1 ÷ 0.337 = 2.97 miles per kWh, 337 Wh per mile and 33.7 ÷ 1.609344 = 20.94 kWh per 100 km (209 Wh per km). In gasoline terms that is 20.94 ÷ 33.7 × 3.785 = 2.35 L/100 km equivalent.
Formulas and notes
- MPGe = 33.7 ÷ (kWh per mile). 33.7 kWh is the EPA energy equivalent of one U.S. gallon of gasoline.
- 1 mile = 1.609344 km and 1 U.S. gallon = 3.785411784 L (exact definitions).
- L/100 km equivalent = kWh per 100 km ÷ 33.7 × 3.785411784.
- MPGe compares energy content, not cost. A car with high MPGe can still cost more or less per mile depending on local electricity and gas prices; see the EV cost per mile calculator.
Planning estimate only, not professional advice. Sources, checked 2026-10-08: Wikipedia, Miles per gallon gasoline equivalent (33.7 kWh per gallon, EPA formula)
What MPGe measures and why 33.7
MPGe, miles per gallon of gasoline equivalent, is the number of miles a vehicle can go on an amount of energy equal to the energy in one gallon of gasoline. FuelEconomy.gov describes it as similar to MPG but expressed for a fuel that is not sold by the gallon, which allows a reasonable comparison between vehicles that use different fuels. The conversion constant is defined in U.S. regulation: 40 CFR 600.002 states that one gallon of gasoline is equivalent to 33.705 kilowatt-hours of electricity. Most converters, including this one, round it to 33.7, which makes the arithmetic clean: 100 MPGe is exactly 33.7 kWh per 100 miles.
The formulas
- kWh per 100 miles = 3,370 ÷ MPGe
- MPGe = 3,370 ÷ kWh per 100 miles
- Miles per kWh = 100 ÷ kWh per 100 miles = MPGe ÷ 33.7
- kWh per 100 km = kWh per 100 miles ÷ 1.609344
- L/100 km equivalent = kWh per 100 km ÷ 33.7 × 3.785411784
The two lengths and volumes are exact unit definitions: 1 mile = 1.609344 km and 1 U.S. gallon = 3.785411784 L, as in NIST's conversion tables.
Reference table
| MPGe | kWh per 100 miles | Miles per kWh | kWh per 100 km | L/100 km equivalent |
|---|---|---|---|---|
| 80 | 42.1 | 2.37 | 26.2 | 2.94 |
| 100 | 33.7 | 2.97 | 20.9 | 2.35 |
| 120 | 28.1 | 3.56 | 17.5 | 1.96 |
| 140 | 24.1 | 4.15 | 15.0 | 1.68 |
Worked examples
From a label. An EPA label that shows 25 kWh per 100 miles converts to 3,370 ÷ 25 = 134.8 MPGe, or 4.0 miles per kWh, or 15.5 kWh per 100 km. Enter 25 with the unit set to kWh per 100 miles, and the tool returns the same figures.
From an owner's trip computer. A car using 17 kWh per 100 km uses 17 × 1.609344 = 27.4 kWh per 100 miles, which is 123.2 MPGe or 3.66 miles per kWh.
Efficiency does not mean cheap. Cost per distance is energy per distance times the price of energy. Illustratively, 25 kWh per 100 miles at $0.12 per kWh costs $3.00 per 100 miles, while a 30 mpg car at $3.50 per gallon costs 100 ÷ 30 × 3.50 = $11.67. Change the electricity price to $0.40 per kWh (a fast-charger-type price) and the EV costs $10.00 per 100 miles. This is why MPGe is an energy metric and not a cost metric. Use the EV cost per mile calculator for cost.
Where the numbers on a vehicle label come from
FuelEconomy.gov explains that the electric vehicle label shows kWh per 100 miles because that figure relates directly to the amount of electricity used, and thus to cost, in the same way that gallons per 100 miles does for gasoline. It also notes that the number is an estimated rate of consumption, and any given vehicle may not match it. Compare vehicles using the same source and the same boundary, since a battery-side figure and a wall-side figure are not interchangeable.
Common mistakes
- Treating a lower number as better in every unit. Lower kWh per 100 miles or per 100 km is better; higher MPGe, miles per kWh and km per kWh are better.
- Mixing miles and kilometres. kWh per 100 km is smaller than kWh per 100 miles by a factor of 1.609.
- Comparing a wall-side charging figure with a battery-to-wheels figure.
Sources
Retrieved
Every link below was opened and read in October 2026. The note after each link says which statement on this page it supports.
- eCFR, 40 CFR 600.002 Definitions (retrieved 2026-10): one gallon of gasoline is equivalent to 33.705 kWh of electricity
- FuelEconomy.gov, Learn more about the electric vehicle label (retrieved 2026-10): MPGe description; kWh per 100 miles as a consumption figure; labels are estimates
- NIST SP 811 Appendix B.9 conversion factors (retrieved 2026-10): 1 mile = 1.609344 km
- NIST SP 811 Appendix B.8 conversion factors (retrieved 2026-10): 1 U.S. gallon = 3.785411784 L
FAQ
What does MPGe mean?
Miles per gallon of gasoline equivalent: the distance a vehicle travels on the amount of electricity with the same energy as one gallon of gasoline, taken as 33.7 kWh.
How do I convert MPGe to kWh per 100 miles?
Divide 3,370 by the MPGe. For example 3,370 ÷ 100 = 33.7 kWh per 100 miles, and 3,370 ÷ 130 = 25.9.
How do I convert kWh per 100 miles to miles per kWh?
Divide 100 by the kWh per 100 miles. 25 kWh per 100 miles is 4.0 miles per kWh.
Is a higher or lower kWh per 100 miles better?
Lower is better: the car uses less electricity to go the same distance. For MPGe and miles per kWh, higher is better.
Does MPGe include charging losses?
The conversion itself does not. Whether a given rating includes losses depends on how it was measured, so use the same source when comparing cars.
What is the EPA conversion factor for MPGe?
The U.S. regulation 40 CFR 600.002 defines one gallon of gasoline as equivalent to 33.705 kWh of electricity. This converter uses the rounded 33.7 kWh figure, so results can differ in the third digit from a label.
Is a higher MPGe always cheaper to drive?
No. MPGe compares energy use and not cost. A very efficient EV charged at an expensive public price can cost more per mile than a less efficient one charged cheaply at home.
How do I convert kWh per 100 km to MPGe?
Multiply by 1.609344 to get kWh per 100 miles, then divide 3,370 by that number. For 17 kWh per 100 km that is 3,370 ÷ 27.36 = 123.2 MPGe.