The EV Calculator
Compare electric car vs petrol or diesel running costs, depreciation, charging and insurance. Calculate total EV running costs over 1, 3 or 5 years using your actual mileage and electricity tariff. Works for any vehicle type including electric SUVs, hatchbacks, crossovers and estates. Enter your car prices to see your exact monthly and total cost of ownership.
Comparing two cars on Autotrader? Use Used EV vs Used Petrol/Diesel - it works for petrol vs EV or diesel vs EV comparisons. Already know you want an EV and want the total cost of ownership or want to compare EVs? Use Buying an EV.
Your Details
Your Petrol Car
The car you're replacing or comparing against
EV Purchase
Most EVs: 3-4 miles/kWh in real-world mixed driving
Ownership & Depreciation
These have the biggest impact on the verdict - set carefully.
What the petrol car would have lost if you'd kept it (an opportunity cost)
Home Charger
Electricity Tariff
Home off-peak: 70% · Home peak: 30% · Public: 0%
EV Running Costs
London CC daily commuters: ~£1,620/yr · ULEZ: £12.50/day × days driven
EV 2 - for comparison
Your Results
Petrol fuel
-EV charging
-Petrol insurance
-EV insurance
-Petrol road tax
-EV road tax
-Petrol servicing
-EV servicing
-Monthly saving switching to EV
-EV price
-Petrol car sale / part exchange
-Home charger
-Net cash outlay on day one
-Break-even on upfront cost
-EV value lost to depreciation
-Petrol would have lost (if kept)
-Depreciation difference
-Total running savings over period
-Ownership verdict - running costs & depreciation only
Hit Calculate to see resultsAll-in verdict - including net upfront outlay
Hit Calculate to see resultsEV 1 charging
-EV 2 charging
-EV 1 insurance
-EV 2 insurance
-EV 1 servicing
-EV 2 servicing
-Monthly cost difference
-EV 1 total cost
-EV 2 total cost
-Depreciation difference
-Which EV wins overall?
-How this calculator works
This calculator models the complete financial picture of EV ownership across three areas: monthly running costs, upfront outlay, and depreciation over your intended ownership period. It works for any electric vehicle - SUVs, hatchbacks, crossovers, estates - and any petrol or diesel car you are comparing against.
To calculate total EV running costs over 1, 3 or 5 years, set your ownership period using the preset buttons, enter your annual mileage, your electricity tariff rate, and your car prices. The calculator handles everything else and updates the results live as you type.
Running costs
Running costs cover four categories for each car: fuel or charging, insurance, road tax (VED), and servicing. The monthly fuel cost for a petrol car is calculated by converting your annual mileage to litres using your MPG figure (1 gallon = 4.546 litres) and multiplying by the fuel price per litre.
Monthly kWh = (monthly miles ÷ efficiency)
Blended rate = (night rate × off-peak home %) + (day rate × peak home %) + (public rate × public %)
Monthly charging cost = monthly kWh × blended rate
How electric car depreciation is calculated
Depreciation uses a compound annual rate applied to the purchase price. If you buy a car for £14,000 at 15%/year, after 3 years its residual value is £14,000 × (1 - 0.15)³ = £8,574, meaning you've lost £5,426. You can set the depreciation rate manually or use the Low, Typical, High presets as a starting point.
In Used EV vs Petrol mode, the petrol car depreciation shows what it would have lost had you kept it (an opportunity cost) view that makes the comparison fair whether you own the petrol car or are comparing two Autotrader listings. The depreciation difference between the two cars is one of the most important figures in the results - worth modelling a few scenarios using the presets.
UK VED rates 2026/27
| Vehicle type | Standard rate | Luxury threshold | Supplement |
|---|---|---|---|
| Petrol / diesel | £200/year | List price > £40,000 | +£440/yr (up to 5 years) |
| Electric (post Apr 2017) | £200/year | List price > £50,000 | +£440/yr (up to 5 years) |
| Electric (pre Apr 2017) | Varies - enter manually | N/A | N/A |
Finance (HP and PCP)
| Finance type | How total cost is calculated | Depreciation? |
|---|---|---|
| Cash | Purchase price + running costs - residual value | Yes |
| HP | Deposit + (monthly × term) + running costs | Yes - you own it at end |
| PCP (returning) | Deposit + (monthly × term) + running costs | No - lender bears residual risk |
| PCP (paying balloon) | Deposit + (monthly × term) + balloon + running | Yes |
All figures are estimates. Depreciation rates vary significantly by model, age, condition and market conditions. This calculator does not constitute financial advice.
About The EV Calculator
The EV Calculator shows the true cost of EV ownership, including depreciation, electricity tariffs, charging costs, insurance, servicing, road tax, and the new 2025 EV VED rates. Calculate total ownership costs over 1, 3, 5 or more years using your real electricity tariff, home vs public charging split, and expected mileage. Unlike basic EV cost calculators, it goes beyond fuel savings to model the full financial picture.
What makes it different
You can model your exact charging setup, setting separate day and night rates and choosing what proportion of charging you do off-peak. Enter a cheap overnight tariff like Octopus Go and watch the numbers change instantly. Public charging costs are modelled separately so high-mileage commuters and those without home charging get an accurate picture rather than a flattering one.
Depreciation is included because it is often the biggest cost nobody talks about. Used EV values have fallen sharply in recent years and ignoring that gives a misleading result. The calculator lets you set Low, Typical, High and Very High depreciation presets for both the EV and the petrol car, so you can stress-test the verdict rather than just accepting a headline saving.
Three modes, one tool
Use Used EV vs Used Petrol to compare two specific cars side by side, whether you are on Autotrader choosing between options or already own the petrol car and want to know if switching makes sense. Use Buying an EV to calculate total cost of ownership for cash, HP or PCP purchases, or to compare two EVs against each other on efficiency, depreciation and overall cost. It works for any vehicle type including electric SUVs, hatchbacks, crossovers and estates.
No sign-up required, no data collected, no ads. Everything runs locally in your browser. Built and maintained in the UK. If you spot an error or have a suggestion, feel free to get in touch.
Frequently Asked Questions
How much cheaper is an EV to run than a petrol car in the UK?
On average, EVs cost around 3-5p per mile to charge at home on an off-peak tariff, versus 12-16p per mile for a typical petrol car. At 10,000 miles per year this can mean fuel savings of £900-£1,300 before accounting for lower servicing costs. Use the calculator with your own mileage and tariff for a personalised figure.
Is it worth buying a used EV in the UK?
It depends on your mileage, charging setup, and the price gap between the used EV and your current car. Higher-mileage drivers with home charging and an off-peak tariff typically see the strongest savings. However, depreciation and insurance costs can offset running cost savings on low-mileage use.
How much does it cost to charge an electric car at home in the UK?
At a standard rate of 24-30p/kWh, a typical EV costs around 6-8p per mile. On an off-peak EV tariff such as Octopus Go (~7p/kWh overnight) this drops to around 2p per mile, a significant saving over petrol. The calculator lets you set separate day and night rates and choose what proportion of your charging you do off-peak.
Do EVs qualify for the OZEV home charger grant?
The OZEV grant provides £350 off a home EV charger for eligible homeowners and flat owners with off-street parking. It is applied at point of purchase through an OZEV-approved installer. Tick the grant checkbox in this calculator to factor it into your upfront costs.
Are electric cars exempt from UK clean air zone charges?
Most UK Clean Air Zones still exempt zero-emission vehicles. The London Congestion Charge 100% EV discount ended in December 2025 for new registrations. Always check the specific rules for your local zone.
What is the EV per-mile road pricing charge?
The UK government has been consulting on replacing fuel duty with a per-mile charge for EVs. No firm rate or timeline has been confirmed, but 3p/mile has been discussed. Ticking the PPM checkbox applies this charge to your results so you can stress-test the numbers.
How accurate are the depreciation figures?
Depreciation is the hardest figure to predict precisely. Used EV depreciation has been notably steep in recent years, with rates of 20-30%/year on some models are not unusual. We recommend modelling a range of rates using the preset buttons to understand the sensitivity of the result.
Can I use this to compare an electric SUV against a petrol SUV?
Yes. The calculator works for any vehicle type - electric SUVs, petrol SUVs, hatchbacks, crossovers or estates. Just enter the asking prices, your mileage, the petrol car's MPG and the EV's efficiency. For a typical electric SUV in mixed driving, efficiency is usually 3.0-3.8 miles per kWh. Enter the insurance and servicing costs for your specific vehicles and the calculator will show monthly running costs, break-even and total cost of ownership side by side.
How do I calculate total running costs for an EV over 3 years?
Set the ownership period to 3 years using the preset button in the Ownership and Depreciation section. Then enter your annual mileage, electricity tariff rates, insurance, servicing, road tax and the car's purchase price. The calculator will show your total running costs over the full 3-year period including depreciation, and compare them against a petrol car if you are using the Used EV vs Petrol mode.
How do I work out the total cost of ownership for an electric car including depreciation?
Use the Buying an EV mode and set your ownership period. Enter the purchase price, your annual mileage, electricity tariff, insurance and servicing costs, and your expected depreciation rate. The calculator adds up all running costs over the period and subtracts the estimated residual value to give you the true total cost of ownership - not just the monthly payment.
Can I compare monthly running costs for a specific mileage - for example 1,200 miles a month?
Yes. Enter 14,400 in the annual miles field (1,200 × 12) and the calculator will show monthly costs based on that mileage. All results including fuel or charging, insurance, servicing and road tax are broken down monthly as well as over your full ownership period.
How does electric car depreciation compare to petrol car depreciation?
Used EVs have generally depreciated faster than equivalent petrol cars over 2023-2025 as supply increased. Typical used EV depreciation rates are 15-25%/year depending on the model, versus 8-15%/year for mainstream petrol cars. However, this varies significantly by model - Teslas and some Korean EVs hold value better than Chinese-brand or older models. Use the depreciation presets in the calculator to model different scenarios and see how much the difference in depreciation affects the overall result.