EV Charging Cost Calculator
What it costs to charge an electric car
Wondering what it costs to 'fill up' an EV? Enter the battery size, your electricity rate and how much you're charging to see the cost — and the cost per mile.
You pay for more than reaches the battery
The obvious calculation is kWh × your electricity rate, and it is wrong by 10 to 18%. Charging is lossy: energy is lost as heat in the charger, the cables and the battery itself, so the meter bills for more than the battery receives.
| Charging efficiency | Into battery | From the grid | Cost |
|---|---|---|---|
| 100% (ignoring losses) | 60 kWh | 60 kWh | $9.60 |
| 90% (typical Level 2) | 60 kWh | 66.7 kWh | $10.67 |
| 85% (Level 1, cold weather) | 60 kWh | 70.6 kWh | $11.29 |
Rough guidance for the efficiency field: Level 2 home charging is around 88 to 92%, slow Level 1 from a household socket is 80 to 85% because the overhead runs for far longer, and DC fast charging is 90 to 95% at the charger but generates considerable heat. Cold weather makes all of them worse, since energy goes into warming the battery before any of it is stored.
Cost to charge electric car, per mile against petrol
EV cost per mile is the figure that compares directly with a petrol car.
| Vehicle | Cost per 100 miles |
|---|---|
| EV at $0.16/kWh | $4.94 |
| Petrol at 40 MPG | $8.75 |
| Petrol at 30 MPG | $11.67 |
| Petrol at 25 MPG | $14.00 |
At an average US residential rate, home charging costs roughly 40% of what a 30 MPG petrol car costs per mile. That gap is the entire running-cost case for an EV, and it lives or dies on your electricity rate.
Your rate decides everything
| Rate | Cost to charge | Per 100 miles | Compares to petrol at |
|---|---|---|---|
| $0.10 (off-peak) | $6.67 | $3.09 | Over 100 MPG |
| $0.16 (US average) | $10.67 | $4.94 | ~71 MPG |
| $0.25 (high-cost state) | $16.67 | $7.72 | ~45 MPG |
| $0.35 (peak rate) | $23.33 | $10.80 | ~32 MPG |
| $0.50 (DC fast charging) | $33.33 | $15.43 | ~23 MPG |
The bottom row is the one that surprises people. Charging exclusively on public DC fast chargers can cost more per mile than a petrol car. Fast charging is a road-trip convenience, not a daily habit — and an EV without home or workplace charging has a much weaker economic case than the headline suggests.
The corollary is that a time-of-use tariff is often the single highest-value change an EV owner can make. Overnight off-peak rates of $0.08 to $0.12 are common, and since the car is parked anyway the saving costs nothing in convenience.
Why 80% rather than 100%
Most manufacturers recommend charging to about 80% for daily use and reserving 100% for long journeys. Lithium-ion cells age faster at high states of charge, and the last 20% also charges much more slowly on a DC charger — the taper above 80% often takes as long as the first 80% did.
Note that cost per mile does not change with charge percentage: charging to 50% costs half as much and gives half the range. What changes is battery longevity and, on a road trip, your time.
- Cold weather can cut usable range 20 to 40%, since heating the cabin and battery draws directly from the pack.
- Highway speed hurts EVs more than petrol cars proportionally, because there is no idling waste to avoid at low speed.
- Battery degradation runs roughly 1 to 2% a year, so an older EV needs slightly more energy per mile.
- Preconditioning while plugged in uses grid power rather than battery, which is both cheaper and better for range.
Compare against a petrol vehicle with the fuel cost calculator, and check what charging adds to your bill with the electricity cost calculator.
How this ev charging cost calculator works out its numbers
Energy into the battery is battery capacity × charge percentage. Energy drawn from the grid is that divided by charging efficiency, and cost is grid energy × your rate. Cost per mile divides cost by range × charge percentage.
- Charging efficiency is optional but matters. Leaving it at 100% understates real cost by 10 to 18%. Typical values are 88 to 92% for Level 2, 80 to 85% for Level 1, and 90 to 95% for DC fast charging.
- Cost per mile is independent of charge percentage, since both cost and miles scale together. Charging to 50% costs half and gives half the range.
- Range is taken as the rated figure at 100%. Real range varies substantially with speed, temperature, terrain and battery age, so cost per mile is optimistic in winter.
- A single flat rate is assumed. Time-of-use tariffs, demand charges and per-minute public charging billing all behave differently.
- Not modelled: battery degradation, charging network subscription fees, idle fees, and any home charger installation cost.
Reviewed September 2026.
Figures reviewed . Every worked example on this page is checked against the calculator above.
EV Charging Cost Calculator: frequently asked questions
How much does it cost to charge an EV?
About $10.67 to charge a 75 kWh battery to 80% at $0.16/kWh with 90% charging efficiency. That is 66.7 kWh drawn from the grid to put 60 kWh into the battery.
Why do I pay for more electricity than the battery holds?
Charging loses energy as heat in the charger, cables and battery. Level 2 home charging is typically 88 to 92% efficient, so you draw about 11% more than reaches the battery. Ignoring this understates the cost.
Is charging an EV cheaper than gas?
At home, considerably. A 75 kWh, 270-mile EV at $0.16/kWh costs $4.94 per 100 miles against $11.67 for a 30 MPG petrol car — roughly 40% of the cost. On public fast charging the advantage can disappear entirely.
Is DC fast charging expensive?
Yes. At $0.50/kWh it works out to $15.43 per 100 miles, which is worse than a 25 MPG petrol car. Fast charging is a road-trip tool, not a daily habit, and an EV without home charging has a much weaker cost case.
How much does it cost to charge an EV per month?
Multiply monthly miles by cost per mile. At 1,000 miles and roughly 5 cents a mile that is about $50 a month at home — typically well under half what the equivalent petrol would cost.
Why charge to only 80%?
Lithium-ion cells age faster at high states of charge, and on a DC charger the last 20% charges very slowly. Cost per mile is unchanged either way; what differs is battery longevity and your time.
Does cold weather affect EV charging cost?
Yes, on both sides. Charging efficiency falls because energy goes into warming the battery, and usable range drops 20 to 40% since cabin and battery heating draw from the pack. Cost per mile rises accordingly.
Should I switch to a time-of-use electricity plan?
For most EV owners it is the highest-value change available. Overnight off-peak rates of $0.08 to $0.12 roughly halve charging cost, and since the car is parked anyway it costs nothing in convenience.