EV Trip Cost Calculator: Electric vs Gas

How the EV Charging Cost Is Calculated

This calculator works out what it costs to charge an electric vehicle for a single trip, based on the distance you plan to drive, the car's efficiency, and your local electricity price. Turning on the gas comparison adds the equivalent cost for a gas-powered car and the dollar difference between the two.

The formula

In metric mode, energy used in kilowatt-hours equals trip distance in kilometers divided by 100, multiplied by the car's efficiency in kWh per 100 km, and the charging cost is that energy figure multiplied by the electricity price per kWh. Switching to imperial mode uses miles and watt-hours per mile instead: energy used equals distance multiplied by efficiency, divided by 1,000 to convert to kWh, then multiplied by the price per kWh. When the gas comparison is turned on, gas cost in metric mode is distance divided by 100, multiplied by fuel use in liters per 100 km, multiplied by the fuel price; in imperial mode it is distance divided by the car's miles per gallon, multiplied by the price per gallon. Savings is gas cost minus charging cost; if that number is negative, the calculator labels it extra cost instead. Alongside the cost, the result panel shows the energy used in kWh, and with the gas comparison on, the gas cost and a savings or extra cost figure, labeled accordingly.

Worked example

A 150-mile trip in an EV rated at 290 Wh per mile uses 43.5 kWh of energy. At an electricity price of $0.16 per kWh, that trip costs $6.96. A gas car covering the same 150 miles at 32 mpg and $3.20 per gallon costs $15.00 in fuel, so the EV trip is $8.04 cheaper.

Charging cost by efficiency

Energy used (kWh) = (Distance in miles x Efficiency in Wh/mi) / 1000
Charging cost = Energy used x Electricity price per kWh