Energy
Compare the energy cost of driving electric with the equivalent gasoline cost.
Enter your numbers to see the answer.
EV vs gas cost calculator guide
Fuel is the cost most drivers feel every month, and this calculator puts an EV and a petrol car side by side on the same distance. Enter monthly miles, EV efficiency in miles per kWh, your electricity price, the petrol car’s miles per gallon, and the pump price. It works out the kWh the EV needs and the gallons the petrol car needs, prices each, and reports the monthly saving—or premium if electricity is expensive where you live. Use the rate from your own bill: US residential averages are around $0.16–0.17 per kWh, but California, New England, and much of Europe sit at $0.30 or more, while off-peak EV tariffs can be under $0.10. For public fast charging, enter $0.40–0.60. The 3.5 mi/kWh default is a mid-size EV in mild weather; many drivers see 3.0 in winter and 4.0 in a compact car in summer. Only energy is compared here—insurance, maintenance, depreciation, tax, and purchase price belong in the total cost calculator.
EV energy cost = miles ÷ EV efficiency (mi/kWh) × electricity rate ($/kWh). Petrol cost = miles ÷ fuel economy (mi/gal) × petrol price ($/gal). Monthly saving = petrol cost − EV energy cost.
Worked example: 1,000 miles a month, 3.5 mi/kWh, $0.16 per kWh, 28 mpg, and $3.50 per gallon. EV energy = 1,000 ÷ 3.5 = 285.7 kWh; cost = 285.7 × $0.16 = $45.71. Petrol = 1,000 ÷ 28 = 35.71 gallons; cost = 35.71 × $3.50 = $125.00. Saving = $125.00 − $45.71 = $79.29 per month, the figure the calculator displays, or about $951 a year. Per mile that is 4.6 cents electric against 12.5 cents petrol. If you charge only at public fast chargers at $0.48 per kWh, the EV side rises to 285.7 × $0.48 = $137.14 and the petrol car is $12.14 a month cheaper.
Miles per month is the distance both cars would cover. EV efficiency is miles per kWh, the figure most trip computers show in North America; convert kWh/100 mi with 100 ÷ (kWh/100 mi), so 30 kWh/100 mi is 3.33 mi/kWh, and Wh/mi with 1,000 ÷ Wh/mi. Fuel economy is US miles per US gallon; multiply a UK mpg figure by 0.833, and convert litres per 100 km with 235.2 ÷ (L/100 km). Prices are currency per kWh and per US gallon; the symbol follows your locale but no exchange rate is applied.
This is a modelled estimate, not a meter reading. Real consumption moves with weather, occupancy, appliance age, standing charges, and tariff structure, and equipment rarely runs at its nameplate rating. Use the figure to compare options against each other, then confirm against your own bill and the manufacturer's specification before committing to a purchase. On this page the figure rests entirely on miles driven, ev efficiency, electricity rate, gas mileage, gas price, market / jurisdiction, effective date, data source, update owner and review date, so start there if the ev vs gas cost calculator returns something you did not expect.
Good to know: home charging loses 10–15% between the wall and the battery, so the meter records more kWh than the car reports; multiply the EV cost by about 1.12 for a fair bill comparison, or use your utility’s actual EV-tariff readings. Do not mix a summer mi/kWh figure with a winter mpg figure. Time-of-use tariffs cut the EV cost sharply only if you actually schedule charging into the cheap window. And if the petrol car you are comparing with is the one you already own, its fuel cost is real while the EV’s saving only arrives after a purchase—use the ownership calculator for that decision.
Energy results depend on tariffs, equipment behavior, region, weather, and installation assumptions. Verify rates and electrical decisions with the utility, manufacturer, or qualified professional.
How it works
Compare the energy cost of driving electric with the equivalent gasoline cost. This tool explains the calculation so you can adjust the assumptions to match your situation.
Worked example
With Miles driven = 1000 mi / month · EV efficiency = 3.5 mi / kWh · Electricity rate = 0.16 $/kWh · Gas mileage = 28 mi / gallon · Gas price = 3.5 $/gallon → $79.29 (monthly EV savings). Change an input above and this example updates with your numbers.
Common questions
Almost always at home. At $0.16 per kWh and 3.5 mi/kWh, electricity costs about 4.6 cents per mile; petrol at $3.50 a gallon and 28 mpg costs 12.5 cents per mile. Public fast charging at $0.45–0.60 per kWh narrows the gap to roughly break-even, so the saving depends on where you plug in.
Multiply monthly miles by your consumption and rate: 1,000 miles at 3.5 mi/kWh needs 285.7 kWh, which is $45.71 at $0.16 per kWh. Add 10–15% for charging losses if you are reading a home meter, giving roughly $50–53 on the actual bill.
At 3.5 mi/kWh, 1,000 miles needs 285.7 kWh; at 3.0 mi/kWh it is 333.3 kWh and at 4.0 it is 250 kWh. For comparison, a typical US household uses about 900 kWh a month, so an EV driven 1,000 miles a month adds roughly a third to the electricity bill.
Use the per-kWh energy charge on your bill including delivery charges, since every extra kWh incurs both. If you have a time-of-use or EV tariff, use the off-peak rate for the share of charging you can schedule overnight—often $0.08–0.12—and the standard rate for the rest.
Yes, roughly linearly. Each $0.50 change in the pump price moves the petrol side by 35.71 × $0.50 ≈ $17.86 a month for 1,000 miles at 28 mpg. Electricity prices move more slowly, which is why EV running costs are more predictable from year to year.