What this EV vs Gas Savings Calculator does
The EV vs Gas Savings Calculator estimates the difference in yearly energy costs for a gas vehicle and an electric vehicle. It uses your annual driving distance, the gas vehicle’s miles per gallon, the gasoline price per gallon, the electric vehicle’s energy use per 100 miles, and the electricity price per kilowatt-hour. The result, Estimated Annual Energy Savings, is the estimated gas energy cost minus the estimated EV electricity cost.
A positive result means the energy-cost estimate for the EV is lower under the numbers you entered. A negative result means the estimated electricity cost is higher. This is a comparison of energy costs only. It does not include vehicle purchase prices, financing, insurance, maintenance, taxes, charging equipment, public charging fees, or resale value. Use it as a transparent planning estimate, not as a promise of savings or a complete ownership-cost comparison.
How to use the EV vs Gas Savings Calculator
Gather figures that match the way you expect to drive. An odometer record or commute log can help estimate annual miles. If your commute varies, include typical workdays as well as regular errands and other driving. For a commute-only comparison, use the miles you expect to drive for that commute over a year.
- Annual driving distance: Enter miles driven in a year. Use the same period for both vehicles.
- Gas vehicle fuel economy: Enter miles per gallon for the gas vehicle you want to compare. A realistic average for your driving is more useful than a best-case rating.
- Gasoline price: Enter dollars per gallon. Choose a price that reflects your planning period and location.
- EV energy use: Enter kilowatt-hours per 100 miles. Use a figure for the EV and driving conditions you have in mind.
- Electricity price: Enter dollars per kilowatt-hour. A bill’s energy charge may differ from its all-in rate, and public charging can have a different price.
After entering the values, read the annual estimate and check the inputs. For example, the calculator assumes the entered fuel economy, energy use, and prices apply across all of the miles. If you drive some miles on free workplace charging or pay different rates at home and on the road, a single electricity price may not represent your actual mix.
How the EV vs Gas Savings Calculator formula works
The calculator first estimates the gas vehicle’s annual fuel spending. It divides annual miles by miles per gallon to estimate gallons used, then multiplies gallons by the gasoline price. It estimates EV electricity spending by converting the entered energy use from kilowatt-hours per 100 miles to energy per mile, multiplying by annual miles, and then by the electricity price.
In compact form, the formula is annual miles × gas price ÷ gas mpg − annual miles × EV kWh per 100 miles ÷ 100 × electricity price. Both parts produce dollars per year. Subtracting the EV estimate from the gas estimate produces the displayed annual difference. The formula uses the inputs directly, so changing mileage or either price changes the estimate in a predictable way.
For a worked example, suppose a commuter drives 12,000 miles per year. Their gas comparison vehicle gets 30 miles per gallon, gasoline costs $3.50 per gallon, the EV uses 30 kWh per 100 miles, and electricity costs $0.16 per kWh. The gas estimate is 12,000 × $3.50 ÷ 30, or $1,400 per year. The EV estimate is 12,000 × 30 ÷ 100 × $0.16, or $576 per year. Subtracting $576 from $1,400 gives an estimated annual energy-cost difference of $824. That result depends on those assumptions and describes energy only.
Use cases for the EV vs Gas Savings Calculator
This estimate can help commuters compare energy costs for a familiar route or annual driving pattern. A driver can enter a typical annual distance, then try a lower or higher mileage figure to see how the estimate changes. Someone considering a longer commute can test the additional miles without assuming the same result applies to every household.
It can also support a discussion about charging access. A commuter who can charge at home may want to use a home electricity rate, then run another estimate using a likely public charging price. The calculator does not model a mix of rates automatically, but you can approximate one by calculating the weighted average price across charging energy if you know the shares. Keep the method consistent when comparing scenarios.
For a fair comparison, select vehicles that could reasonably serve the same travel needs. A small efficient gas car and a larger electric vehicle may differ in comfort, cargo capacity, range, and purchase cost. This calculator isolates energy spending to make that piece easier to inspect. It does not decide whether either vehicle fits a particular commuter’s needs.
Other factors to consider when calculating EV and gas costs
Real-world energy use varies. Temperature, speed, hills, traffic, tires, vehicle load, and driving style can affect fuel economy and EV efficiency. Stop-and-go commuting may affect the vehicles differently, while cold weather can reduce an EV’s range and increase energy use. Published efficiency figures are useful starting points, but the figures for your route may differ.
Electricity billing can also be more complicated than one price per kilowatt-hour. A utility bill may include fixed charges, time-of-use rates, or other components. Some public charging stations price by time or session, and local rules may affect how charging is billed. If those charges matter to your decision, calculate a representative effective price from your own records and make clear which costs it includes.
Finally, energy is only one part of ownership. Purchase price, incentives, financing, repairs, maintenance, insurance, registration, charging installation, and resale value can all affect a broader comparison. Those costs depend on individual circumstances and may change over time. For a fuller budget, gather current figures for both vehicles and compare them over the same ownership period. Avoid treating this annual energy estimate as a total-cost calculation.
FAQ
Does a positive result mean an EV will save me this exact amount?
No. It means the entered assumptions produce that estimated difference in energy spending for one year. Actual mileage, prices, efficiency, and charging patterns can vary. The result excludes costs beyond gasoline and electricity.
Should I use the vehicle’s advertised efficiency?
You can use an advertised figure as a starting point, but your route and conditions may lead to different efficiency. If you have reliable records for a comparable vehicle or route, those may better represent your planning assumptions. Use consistent units and make sure EV energy use is stated per 100 miles.
How do I account for home and public charging?
The calculator accepts one electricity price. If you charge at more than one rate, estimate a blended price based on the energy charged at each rate, or run separate scenarios to see how the assumptions affect the result. Include public charging charges in the figure when you can express them as a comparable cost per kilowatt-hour.
Does the estimate include the cost of installing a home charger?
No. The formula includes electricity spending only. Charger equipment and installation, along with any applicable vehicle or ownership costs, need to be considered separately using figures relevant to your situation.
Can the result be negative?
Yes. A negative estimate means that, under the entered assumptions, the calculated EV electricity expense is higher than the gas vehicle’s fuel expense for the year. Check that your prices and efficiency figures use the stated units, then consider how sensitive the result is to changes in mileage and energy rates.