Gas vs Electric Car Calculator

How the Gas vs Electric Comparison Works

We calculate the per-mile fuel cost for both drivetrains using real data: your EV's EPA efficiency rating in kWh/100 miles multiplied by your local electricity rate, versus your gas car's MPG rating divided into the current gas price. CO2 emissions use the EPA's standard of 8,887 grams per gallon of gasoline and 0.86 lbs of CO2 per kWh of electricity (the U.S. grid average). The electric side is the same math as the cost to charge an electric car calculator, which also shows the cost of a full charge.

Why EV Fuel Costs Are Lower

Electric motors convert 85 to 90% of electrical energy into motion, while internal combustion engines convert only 20 to 35% of gasoline energy. This efficiency gap means EVs travel 3 to 4 miles per kWh equivalent, compared to gas cars at roughly 1 mile per kWh equivalent. Home electricity at the US average of 18.19 cents per kWh is also far cheaper per unit of energy than gasoline. If the car you are weighing is a hybrid rather than an EV, the hybrid vs gas calculator runs the per-mile math with the hybrid price premium and the payback year.

What This Comparison Does Not Include

• Repairs and tires: the fuel plus maintenance tiles above count scheduled maintenance only (no oil changes, fewer brake jobs thanks to regenerative braking, no transmission service), which saves about $511 a year at your miles. Unplanned repairs and tire wear are not counted.
• Financing and resale value: the break-even above compares the price gap with running costs only; loan interest and what each car is worth when you sell it are not counted.
• Insurance differences: EV insurance typically costs 10 to 15% more due to higher repair costs.
• Battery degradation: most EV batteries retain 90% or more capacity after 200,000 miles, but replacement costs $5,000 to $15,000 if needed.