Cost per Mile Comparison
Updated .
This tool compares the energy cost per mile or kilometre and the annual energy cost of your Tesla with a gasoline car, using your own electricity price, your own Wh per mile or km, the fuel price and the comparison car’s fuel economy. The comparison car’s figures are whatever you enter; the tool does not assume a model. It counts energy only, not insurance, tires, maintenance or depreciation.
How it works
The tool converts everything to a cost per unit of distance, then scales it to a year:
- Tesla: cost per mile or km = Wh per mile or km ÷ 1000 × price per kWh.
- Comparison car, miles: cost per mile = price per gallon ÷ mpg.
- Comparison car, kilometres: cost per km = litres per 100 km ÷ 100 × price per litre.
- Annual cost = cost per mile or km × distance per year, for each car.
- Difference = the comparison car’s annual cost − the Tesla’s.
The comparison car is yours to define. The mpg or litres per 100 km figure is whatever you type in, so use the real-world figure from the car you are comparing against rather than a brochure value. Likewise the Wh per mile or km should come from your own car’s energy screen. If you charge mostly at home, an honest electricity price blends your off-peak rate with any public charging you do. The charge cost calculator can help you work that out.
What this leaves out. It compares energy cost only. Insurance, tires, servicing, depreciation, registration fees and any charger installation are not included, so a lower energy cost is not the same as a lower total cost of ownership. Fuel-economy figures and prices also move over time, so rerun the comparison when yours do.
Worked example
Suppose, in miles, an electricity price of 0.15 per kWh, a consumption of 280 Wh per mile, a gasoline price of 3.50 per gallon, a comparison car at 30 mpg, and 12,000 miles a year.
Tesla: 280 ÷ 1000 × 0.15 = 0.042 per mile, or 0.042 × 12,000 = 504.00 a year. Comparison car: 3.50 ÷ 30 = 0.117 per mile (0.1167 before rounding), or about 1,400.00 a year. Difference: 1,400.00 − 504.00 = 896.00 a year less in energy cost for the Tesla.
The result swings with the inputs. Raise the electricity price to 0.30 and the Tesla’s cost per mile doubles to 0.084, so the annual gap falls from 896 to 392. Compare against a 50 mpg car instead and the comparison cost falls to 0.07 per mile, 840 a year, which narrows the gap further. These numbers are illustrative arithmetic, not a claim about any particular Tesla or comparison car.
Frequently asked questions
Which comparison car should I use?
Whichever you are actually weighing up, or the car you drive now. Enter its real-world fuel economy and the fuel price you pay; the tool does not assume any model.
Does this include insurance, maintenance and depreciation?
No. It compares energy cost only, so it shows the running-cost gap from fuel and electricity, not the total cost of owning either car.
How do I get a fair electricity price?
Blend what you pay at home with what you pay at public chargers, weighted by how much you charge in each place. The charge cost calculator helps you work out a cost per charge from your own figures.
Can I use kilometres and litres?
Yes. Choose kilometres in the unit box, then enter the fuel price per litre and the comparison car’s litres per 100 km.
What if my result says the Tesla costs more?
That can happen with expensive electricity or a very efficient comparison car. The tool reports it plainly so you can see which input is doing the work.
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