What is the Home EV Charging Cost Calculator?
This calculator estimates how much it costs to charge an electric vehicle (EV) at home. By combining how far you drive, how efficiently your car uses energy, and the price you pay for electricity, it shows your total charging cost and your cost per mile. It works with any currency and any region — just enter your local electricity rate per kilowatt-hour (kWh).
How to use it
Enter three values: the miles driven over the period you want to measure (a trip, a week, a month, or a year), your EV's efficiency in miles per kWh (commonly 3 to 4 mi/kWh), and your electricity price per kWh from your utility bill. The result shows total cost, the kilowatt-hours consumed, and the cost per mile.
The formula explained
First, energy used equals miles divided by efficiency: a car that travels 3.5 miles per kWh and drives 1,000 miles uses \( 1000 / 3.5 \approx 285.71 \) kWh. Multiply that by the electricity price to get the cost. The cost per mile is simply the total cost divided by the miles driven, a handy way to compare against a gas car.
$$\text{Cost} = \frac{\text{Miles}}{\text{Efficiency (mi/kWh)}} \times \text{Price (\$/kWh)}$$
Worked example
Suppose you drive 1,000 miles, your EV gets 3.5 mi/kWh, and electricity costs $0.15/kWh. Energy used = \( 1000 / 3.5 = 285.71 \) kWh. Cost:
$$285.71 \times \$0.15 = \$42.86$$
Cost per mile = \( \$42.86 / 1000 \approx \$0.0429 \). That's noticeably cheaper than refueling most gasoline cars over the same distance.
FAQ
How do I find my EV's efficiency? Check your dashboard's energy display (mi/kWh) or your car's spec sheet. Most modern EVs average 3–4 mi/kWh; efficiency drops in cold weather and at high speeds.
Does this include charging losses? No — real-world charging is about 85–90% efficient, so actual energy drawn from the wall is a bit higher. To be conservative, lower your efficiency figure slightly (e.g. use 3.2 instead of 3.5).
What electricity price should I use? Use your marginal or off-peak rate per kWh from your utility bill. Many EV owners charge overnight on cheaper time-of-use rates.
