EV Charging Cost vs Gas Calculator

How to use the EV vs Gas Cost Calculator

Choose a currency, enter a comparison distance and add the distance you normally drive in a year.

Enter the EV's real-world efficiency and the electricity price you usually pay at home. Then enter the gasoline vehicle's fuel economy and pump price.

The main result compares the two vehicles over the same distance and shows the annual electricity-versus-gasoline cost difference when annual driving is available.

Open Additional when you need to model public charging, identify whether the EV efficiency already includes charging losses, or add optional purchase-price and maintenance differences.

Compare the same driving distance

A useful EV-versus-gas comparison starts by making both vehicles travel the same distance.

The calculator converts the selected EV efficiency into electricity required for that distance and converts the gasoline efficiency into litres required for the same distance.

It then applies the entered energy prices independently before comparing the two costs.

Results are also normalized to 100 kilometres or 100 miles, which makes differently sized trips easier to compare.

Use real-world efficiency when possible

Rated efficiency is useful for comparison, but your own consumption can be more representative when you already drive the vehicle.

Speed, weather, cabin heating or cooling, elevation, traffic, payload, tyre pressure and driving style can all change real energy or fuel consumption.

For an existing vehicle, a longer period of charging records, trip history or fuel receipts is generally more representative than one unusually efficient or inefficient journey.

When comparing two candidate vehicles, use figures measured under reasonably comparable conditions.

EV efficiency units supported

The calculator accepts both consumption-style and efficiency-style EV figures.

kWh/100 km, kWh/100 mi and Wh/km describe energy consumed for a fixed distance, so lower numbers are more efficient.

km/kWh and mi/kWh describe distance travelled for each kilowatt-hour, so higher numbers are more efficient.

Choose the unit used by your source rather than manually converting it first. This avoids unnecessary rounding.

Vehicle-side vs meter-side EV energy

The most important EV input distinction is where the efficiency measurement is taken.

Vehicle-side or battery-side consumption describes energy used by the vehicle. If that is your source, electricity lost while charging still has to be purchased and the calculator adds the entered charging loss.

Meter-side consumption already represents electricity drawn from the wall. In that case, the purchased electricity is known and the calculator does not increase it again.

Choosing the wrong boundary can double-count charging loss or omit it entirely.

Using EPA kWh/100 mi figures

The U.S. EPA electric-vehicle label reports an electricity consumption rate in kilowatt-hours per 100 miles.

EPA documentation explains that the label value is based on electricity required from the outlet and includes wall-to-vehicle charging losses.

When you use that EPA-label kWh/100 mi figure in this calculator, choose Meter / wall electricity so charging loss is not added a second time.

This is different from a vehicle trip computer that reports only energy consumed after electricity has reached the vehicle.

What charging loss means

Charging an EV is not perfectly efficient. Some electricity drawn from the grid is lost before it becomes usable energy in the vehicle.

When the entered efficiency is vehicle-side, the calculator divides vehicle energy by the remaining charging efficiency to estimate electricity purchased from the meter.

For example, if the vehicle needs 18 kWh and charging loss is 10%, approximately 20 kWh must be purchased because 18 is 90% of 20.

When the efficiency is already meter-side, the entered kWh already describes purchased electricity. The loss setting is then used only to estimate the vehicle-side portion.

Home charging and public charging

Home and public charging can have very different electricity prices, so the calculator can blend them instead of forcing one universal rate.

Public charging percentage means the share of purchased charging energy obtained publicly, not the percentage of charging sessions.

For example, a person could make many short home-charging sessions and only a few public sessions while still buying a large share of annual electricity publicly.

The calculator multiplies each charging share by its corresponding price and combines the two into one energy-weighted electricity rate.

Use an effective public charging price

Public charging prices can involve more than a simple energy rate.

If a predictable subscription, session charge or other recurring fee materially changes what you pay per kWh, you can incorporate it into an effective public electricity price before entering it.

Do not spread highly irregular parking penalties, idle fees or unrelated costs across electricity unless doing so reflects the scenario you actually want to model.

How gasoline efficiency is handled

Gasoline efficiency can be entered as L/100 km, km/L, US mpg or Imperial mpg.

US and Imperial gallons are different sizes, so the calculator treats US mpg and Imperial mpg as separate units rather than assuming they are interchangeable.

Fuel price can likewise be entered per litre, per US gallon or per Imperial gallon.

Internally, the fuel requirement and price are normalized before calculating gasoline cost for the comparison distance.

What the main result tells you

The main result answers which vehicle costs less for electricity or gasoline under the assumptions entered.

When annual distance is present, the headline uses the annual energy-cost difference. Without annual distance, it falls back to the selected trip.

A positive savings result means the EV's electricity cost is lower. A reverse result means the gasoline vehicle costs less for energy.

The comparison bar shows the actual magnitude of EV and gasoline energy spending rather than treating one vehicle type as automatically cheaper.

Cost per kilometre, mile and 100 distance units

Cost per kilometre or mile is useful when you want to apply the result to a different driving distance.

Cost per 100 km or 100 miles provides a larger and often easier-to-read normalized comparison.

These values describe electricity and gasoline spending only. They do not include the full cost of owning the vehicle.

Annual EV and gasoline cost

Annual distance scales the normalized running cost to your expected yearly driving.

The annual projection reports electricity purchased by the EV, gasoline consumed by the comparison vehicle and the resulting energy or fuel spending.

Monthly values are the annual projection divided by 12. They are planning averages rather than a prediction that every month contains identical driving.

Changing annual distance changes total annual savings but does not change which vehicle has the lower energy cost per kilometre or mile when all other assumptions remain constant.

Break-even electricity price

Break-even electricity price answers how expensive the blended charging rate could become before the EV and gasoline vehicle have equal energy cost.

It equals gasoline cost over the comparison distance divided by the electricity the EV would purchase for that distance.

Below that rate, the EV costs less for energy under the entered efficiency and fuel-price assumptions. Above it, gasoline costs less.

The threshold changes whenever vehicle efficiency or gasoline price changes.

Break-even gasoline price

The gasoline break-even calculation works in the opposite direction.

It finds the pump price that would make gasoline spending equal to the EV's electricity spending for the same distance.

The result is returned using the gasoline-price unit selected in the calculator, whether that is per litre, US gallon or Imperial gallon.

Optional EV purchase-price payback

The Additional section can include an EV purchase-price difference. Enter EV price minus gasoline-vehicle price.

A positive value means the EV costs more upfront. A negative value means the EV is already cheaper at purchase under the entered comparison.

When the EV has a positive upfront premium and positive annual savings, simple payback divides that premium by annual energy savings plus the entered maintenance savings.

The calculator also converts that payback period into an estimated driving distance using the annual-distance assumption.

Maintenance difference is optional

Enter annual maintenance savings only when you have a reasonable vehicle-specific assumption.

A positive amount means the EV is expected to cost less to maintain each year; a negative amount means the gasoline vehicle is expected to have the maintenance advantage.

Leaving the field empty keeps the core comparison focused on electricity and gasoline.

The input is deliberately a single annual difference rather than a detailed repair forecast.

Simple payback is not total cost of ownership

The optional payback result is intentionally narrow.

It does not model depreciation, financing interest, insurance, taxes, registration, incentives, charger installation, battery degradation, tyres, repairs, resale value or the time value of money.

A vehicle that has the shorter simple payback is therefore not automatically the lower-cost vehicle over its entire ownership life.

Use a full vehicle-specific ownership analysis when those costs matter to the decision.

Why an EV can cost more to run

An EV is not guaranteed to have the lower energy cost in every scenario.

High public-charging prices, poor EV efficiency, substantial charging losses, inexpensive gasoline or an especially efficient gasoline vehicle can reverse the comparison.

That is why the calculator uses the prices and efficiencies entered instead of applying a fixed assumption that one drivetrain always wins.

Run more than one scenario

Energy prices and efficiency are not fixed forever, so one result should not be treated as certainty.

Try a home-heavy charging case, a mixed charging case and a public-heavy case if your future charging pattern is uncertain.

You can also test lower winter EV efficiency, a higher gasoline price, or different annual driving.

A range of realistic scenarios is often more useful than one optimistic point estimate.

What this calculator includes and excludes

The calculator is primarily a running-energy-cost comparison with an optional simple-payback layer.

It deliberately does not mix emissions, financing, depreciation and every ownership expense into the headline result.

Keeping those concepts separate makes it clear which assumptions actually produced the EV-versus-gas energy-cost difference.

EV and gasoline cost formulas

Both vehicles are converted to energy or fuel required for the same distance. Charging loss is added to purchased electricity only when the EV efficiency is vehicle-side.

$\eta$

Charging efficiency as a decimal

$L$

Entered charging-loss percentage

$E_v$

Vehicle-side EV energy for the comparison distance

$E_m$

Electricity purchased from the meter for the comparison distance

$E_{l}oss$

Electricity lost between meter and vehicle

$P_h$

Home electricity price per kWh

$P_p$

Public electricity price per kWh

$S$

Public charging share as a decimal

$P_e$

Blended electricity price per kWh

$C_h$

Home charging cost

$C_p$

Public charging cost

$C_{E}V$

Total EV electricity cost

$G$

Gasoline required for the comparison distance

$P_g$

Gasoline price per litre after unit conversion

$C_g$

Gasoline cost for the comparison distance

$\Delta C$

Gasoline cost minus EV electricity cost

$D_a$

Annual driving distance

$A_E$

Annual energy-cost savings

$M$

Entered annual EV maintenance savings

$A_T$

Annual energy plus maintenance savings used for simple payback

$\Delta P$

EV purchase price minus gasoline-vehicle purchase price

$Y$

Simple payback period in years

$D_{B}E$

Estimated driving distance at simple payback

Examples

Frequently Asked Questions

References

• U.S. Department of Energy AFDC — Charging Electric Vehicles at Home
• U.S. Department of Energy AFDC — Vehicle Cost Calculator Assumptions and Methodology
• U.S. Department of Energy AFDC — Electric Vehicle Benefits and Considerations
• U.S. EPA — Fuel Economy and EV Range Testing
• U.S. EPA — Text Version of the Electric Vehicle Label
• U.S. EPA — Interactive Electric Vehicle Label