How the ev vs gas calculator works
Fuel cost is miles driven divided by efficiency, times the price of energy. Gas cars burn gallons and EVs use kilowatt-hours; a share of the electricity drawn from the wall is lost as heat while charging.
EV cost = Miles ÷ (mi/kWh) ÷ (1 − charging loss) × Electricity rate
Break-even gas price = EV cost ÷ gallons the gas car would use
Most EVs travel 3 to 4 miles per kWh; the EPA window sticker lists consumption as kWh per 100 miles (divide 100 by it to get mi/kWh). Home charging losses are usually 10% to 15% on a Level 2 charger. US residential electricity averaged around 17 cents per kWh in recent EIA data, but rates vary from under 12 cents to over 30, and DC fast charging often costs 40 to 60 cents.
Worked example
Driving 12,000 miles a year in a 28 MPG car at $3.50 a gallon costs $1,500. An EV at 3.5 mi/kWh with 10% charging losses uses 3,810 kWh, or $648 at 17 cents. The EV saves about $852 a year, or $4,262 over five years. Gas would have to fall to about $1.51 a gallon for the costs to match.
Frequently asked questions
How much does it cost to charge an EV at home?
Multiply the kWh you use by your rate. At 17 cents per kWh and 3.5 mi/kWh, charging costs about 5 cents a mile.
What is a good mi/kWh for an EV?
Around 3 to 4 mi/kWh is typical; efficient sedans can exceed 4, while large trucks and SUVs can fall below 2.5.
Are EVs cheaper to maintain?
Usually. They have no oil changes and less brake wear thanks to regenerative braking, though tires can wear faster.
Does public fast charging change the math?
Yes. At 50 cents per kWh, the EV in the example would cost about $1,900 a year, more than gas.
Updated October 2026. Results are estimates for education, not financial or medical advice. All math runs in your browser; nothing you type is sent anywhere.