How to use the hybrid vs gas break-even calculator
- Enter how much more the hybrid costs than the gas model of the same car.
- Enter the fuel economy of both cars in miles per gallon.
- Enter the miles you drive in a year and the price of a gallon of fuel.
- Read the break-even in years and miles, the yearly fuel cost of each car and the table of savings by year.
Formula
Yearly fuel cost = miles / mpg x price per gallon
Yearly saving = gas model cost - hybrid cost
Break-even years = extra price / yearly saving
Break-even miles = break-even years x miles a year
The calculator needs the hybrid to be more efficient than the gas model. If the two figures are equal or reversed there is no saving to pay the premium back.
A $2,800 premium for 48 mpg instead of 30 mpg
At 12,000 miles a year and $3.60 a gallon the gas model burns 400 gallons, which costs $1,440. The hybrid burns 250 gallons, which costs $900. The saving is $540 a year.
The premium of $2,800 divided by $540 is 5.2 years, which is about 62,222 miles. The table shows the position year by year: after five years the net figure is still ($100.00) behind, and in year 6 it turns to $440.00 ahead.
What drives the break-even
Three things move the answer: the size of the premium, the gap between the two fuel economy figures and the number of miles you drive. A short commute stretches the break-even out, while a long one pulls it in. The gap in efficiency matters more at low mpg than at high mpg, because the fuel used is miles divided by mpg and a few mpg at the low end changes the gallons a lot.
Fuel prices change, so try the presets for a higher price and fewer miles. If the break-even is longer than you expect to keep the car, the premium is unlikely to pay back from fuel alone.
What is left out
Insurance, maintenance, taxes, incentives, financing and resale value can all differ between a hybrid and a gas car. The Total Cost of Car Ownership Calculator puts those on one page. If you are weighing an electric car, the EV vs Gas Cost Calculator compares running costs, and the Fuel Cost Calculator prices a trip. To find your real mpg, use the MPG Calculator.
To see what your fuel burn means in emissions, the Fuel Combustion CO2 Calculator turns gallons into kilograms of carbon dioxide.
Assumptions and limits
- Both cars are driven the same miles each year with the same fuel price.
- The mpg figures are what you expect in your own driving. Label values are often higher than real use.
- The fuel price and the premium are examples. Use the figures you are quoted.
- The saving is constant from year to year. Price changes and inflation are not modeled.
Frequently asked questions
What if the hybrid saves money but the break-even is very long?
Then fuel alone does not justify the premium within the years you expect to own the car. Other things, such as comfort or emissions, may still matter to you.
Can I use liters and kilometers?
Convert your figures first with the fuel economy converter, then enter miles per gallon, miles and a price per gallon.
Why does the table show amounts in parentheses?
Parentheses mean a negative number, so ($2,260.00) means you are still $2,260.00 behind after paying the premium and counting the fuel saved.
Does a higher fuel price shorten the break-even?
Yes. Every gallon saved is worth more, so the yearly saving grows and the premium is repaid sooner.