EV Charging Cost Calculator
Estimate your daily and monthly charging costs. Compare home vs. public charging rates.
Last Updated: January 2026
What this calculator does
Estimate EV driving cost using distance, efficiency, electricity price, and charging losses. The tool reports cost per mile or kilometer and monthly totals for home vs public charging.
Inputs explained
- Currency: Symbol used to display costs (USD, EUR, GBP, and more).
- Daily driving distance: Miles or kilometers driven per day.
- Days driven per month: Number of days you typically drive.
- Vehicle efficiency: Choose the unit you know (mi/kWh, Wh/mi, kWh/100mi, kWh/100km, or Wh/km).
- Home electricity rate: Price per kWh from your utility bill.
- Charging loss percent: Energy lost to heat and conversion, entered as a percent.
- Public charging markup percent: Extra percent added to the home rate to model public charging prices.
How it works / Method
- Convert your efficiency to kWh per selected distance unit (mi or km).
- Adjust for charging losses to estimate grid energy per mile or kilometer.
- Multiply by your electricity rate to get cost per distance and cost per 100 units.
- Scale by monthly distance and apply public markup to compare home vs public totals.
Formula(s) used
kWh_per_unit = convert(efficiency)
grid_kWh_per_unit = kWh_per_unit / (1 - loss%/100)
cost_per_unit = grid_kWh_per_unit * rate
monthly_distance = daily_distance * days_per_month
monthly_kWh = monthly_distance * grid_kWh_per_unit
monthly_cost_home = monthly_kWh * rate
monthly_cost_public = monthly_kWh * rate * (1 + markup%/100)
savings = monthly_cost_public - monthly_cost_home
Units: distance in mi or km, energy in kWh, rate in currency per kWh. Assumes losses and markup remain constant during the month.
Inputs
Results
Cost per mi
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Cost per 100 mi
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Monthly Cost (Home)
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Monthly Cost (Public)
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Potential Monthly Savings
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Step-by-step example
Example inputs: 30 miles per day, 22 driving days per month, 3.5 mi/kWh efficiency, $0.15 per kWh home rate, 10% charging loss, and a 30% public charging markup.
- Convert efficiency: 1 / 3.5 = 0.286 kWh per mile.
- Account for losses: 0.286 / 0.90 = 0.317 kWh per mile from the grid.
- Cost per mile: 0.317 * $0.15 = $0.048 per mile.
- Monthly distance: 30 * 22 = 660 miles.
- Monthly home cost: 660 * 0.048 = $31.43.
- Public rate: $0.15 * 1.30 = $0.195 per kWh, monthly public cost about $40.86.
- Estimated monthly savings: $40.86 - $31.43 = $9.43.
Use cases
- Budget monthly charging costs for commuting and errands.
- Compare home charging with public charging when planning trips.
- Test how efficiency changes affect cost per mile or kilometer.
- Estimate savings after switching to a time of use electricity plan.
- Cross-check results with the EV vs ICE fuel cost calculator.
Assumptions & limitations
- Efficiency is treated as a steady average.
- Temperature, HVAC use, and tire pressure can increase energy use beyond rated values.
- Charging loss varies by charger type and battery temperature; a single percent is used here.
- Public pricing may include fees; markup is a simplification.
- Electricity prices are a single blended rate.
- Battery aging and regeneration effects are not modeled directly.
Disclaimer: Results are estimates for planning only. Real world charging cost and range vary by conditions and driving behavior.
Frequently Asked Questions
Honestly, the math here is simpler than most people expect. Take your electricity rate, say ■8 per kWh, and multiply it by how many kWh your EV burns per mile. So if your car uses 0.25 kWh per mile, that's ■2 per mile straight up. But here's the catch I always tell my customers — chargers aren't 100% efficient. There's about 8-12% loss between the wall and your battery. So bump that figure up by roughly 10% to get a realistic per-mile cost. That gives you the truth, not the brochure number.
I sit down with every customer and run this number for them. The formula is: monthly miles × your car's kWh per mile × your electricity rate × 1.10 for charging losses. Say you drive 1,500 km a month in a car that uses 0.18 kWh per km, and your tariff is ■7. That works out to about ■2,080 a month. People usually expect it to be higher. Compare that to ■15,000+ on petrol for the same distance, and you'll see why folks switch. Just remember to use your actual tariff, not the slab average.
This is the hidden number nobody talks about in ads. When you plug in, your meter reads more energy than what actually ends up in the battery. Onboard charger conversion, cable resistance, battery cooling — they all eat power. A 10% loss means if your battery needed 50 kWh, the meter clocks 55 kWh. You pay for that extra 5. Over a month it adds up. I always advise customers to factor in 8-12% on top of their battery-energy math so the bill doesn't surprise them later. Better to plan with the real number.
Almost always, yes — sometimes by a wide margin. Home tariffs in most places run ■6-9 per kWh, while public DC fast chargers can charge ■18-25 per kWh, and that's before any session or idle fees. I tell my customers: think of public charging as a convenience tax. It's there when you need it on a long trip, but for daily driving, your home wallbox pays for itself fast. The exception is workplace chargers or free supermarket points — those obviously beat home rates. Run the numbers for your weekly pattern before deciding what to lean on.
Use the actual rate from your latest bill, not what you remember or what someone told you. In India, residential tariffs work in slabs — your marginal rate (the rate for the next unit you consume) is what matters, since EV charging adds on top of your existing consumption. If you're on a time-of-use plan, use the rate for whichever window you actually charge in. Don't average peak and off-peak unless your charging spans both. For public charging, pull the receipt and divide total cost by kWh delivered — that's your real effective rate.
Quick math: take your kWh per 100 miles and multiply by the electricity rate. A typical EV uses around 28-32 kWh per 100 miles. At ■8 per unit, that's roughly ■230-260 for 100 miles, or about ■140-160 per 100 km in metric. Add 10% if you want the bill-accurate figure including charging losses. Compare that to a petrol car doing 15 kmpl at ■105 per litre — you're looking at ■700 for the same distance. The savings are real, but always run the numbers with your specific car's efficiency, not a generic average.
The trick is getting both to the same unit — effective rupees per kWh delivered. For home, it's just your tariff plus any fixed charges spread across your usage. For public, divide the total session cost (energy + idle + connection fees + taxes) by the kWh that actually went into your battery. You'll often find a 15 kWh public session at ■400 works out to ■26 per kWh effective, versus ■8 at home. Then multiply each by your car's kWh per mile to get cost per mile. Apples to apples — that's the only fair way.
Absolutely, and many of my corporate customers ask this. Just plug in the workplace tariff, the energy added per session, and any time-based fees your office charges. Some companies subsidize and charge a flat ■3-5 per kWh, others pass through the full commercial tariff which might be ■10-12. A few offer it free as a perk. Treat each session like a public charging event — note the kWh added, the duration, and the price model. Add it up over a month and compare against what you'd spend charging the same energy at home. The answer often surprises people.
Time-of-use can be a game changer if you actually shift your charging behaviour. Off-peak rates — typically late night to early morning — can be 30-50% cheaper than peak rates in many regions. So if your normal tariff is ■9 and your off-peak is ■5, charging overnight cuts your fuelling cost almost in half. The catch is discipline. If you plug in at 7 PM peak time out of habit, you're paying premium. Use a smart charger or your car's scheduled charging feature to start automatically at the off-peak window. That's where the real savings live.
For cost math, kWh per mile or kWh per 100 miles is the cleanest unit because electricity bills come in kWh. Miles per kWh is fine for range talk but flips the math on its head when you're calculating cost. If your manual gives you Wh per mile, divide by 1000 to get kWh per mile. If it says miles per kWh, divide 1 by that figure. Once everything is in kWh per mile, you just multiply by your tariff. I prefer kWh per 100 miles in customer conversations — the numbers are easier to picture.
Sources & references
- U.S. Energy Information Administration: Measuring electricity - Defines kW and kWh used in cost calculations.
- DOE Alternative Fuels Data Center: EV charging options for consumers - Charging level overview and typical power ranges.
- U.S. EPA: Plug-in electric vehicle charging basics - Explains charging behavior and real world charging speeds.
- U.S. DOE Energy Saver: Fuel economy in cold weather - Shows how temperature and accessories affect energy use.
- Schema.org: FAQPage, WebPage, and BreadcrumbList - Structured data definitions used on this page.