How we calculate

How CarDep works out what a car costs per month, where the numbers come from and how the value grade is set.

The monthly cost is everything you pay for the car while you own it, divided by the number of months: depreciation, fuel or electricity, servicing and repairs, insurance and road tax. Loan interest is not included. The model pages assume 5 years of ownership and 12,500 km a year. In the calculator you can change everything.

Depreciation
Purchase price minus the estimated residual value. How fast each model loses value is worked out from what the cars cost in ads today, model year by model year. The first year has the biggest drop, then the rate slows. The residual value also depends on how far you drive: for every 10,000 km more than a typical car of the same age when you sell, the car is worth about 2 percent less, and the other way round. That is how much ad prices differ for the same model and model year.
Used cars
Used prices are based mainly on ads on Blocket, Sweden's largest marketplace. In October 2026 we went through about 41,700 Swedish ads for every model year on AutoUncle, which shows which site each ad is on. About half, 20,900 ads, are on Blocket. For each model year we use the median price of the Blocket ads when there are at least five, which is the case for 73 percent of the model years. Otherwise we use the other Swedish ads from dealers and sites such as Bytbil and Wayke, or prices from BilKoll collected in August–October 2026. Where a model year still has too few Swedish ads, we use ads from Finland, and for electric cars also from Denmark. Their prices are converted to the Swedish price level using twelve models sold in all three countries. Danish petrol and diesel cars are left out, because the registration tax makes them too expensive to compare. The purchase price of a used car starts from the ads for that model year: we compare each ad with the new price of the same engine and trim and convert the median to the version you choose. Where a model year has few ads, a depreciation curve for the whole model is weighed in, and Blocket ads count for more than others. The price never goes below what the cheaper ads with the same or more mileage cost (the cheapest fifth for the engine, or tenth for the whole model year), so you should be able to find a car at that price. Versions that hardly appear in a model year's ads are not picked automatically. Mileage is the median in the ads for that model year. Where a model year has few ads, the typical mileage for the model and age is weighed in, and an older model year always has covered more than a newer one. The price is adjusted for the difference from the advertised cars' mileage. Ad prices are asking prices, and the final price may be lower. Servicing and repairs get more expensive with age and once the warranty has run out. Malus tax is only paid for the years left of the car's first three. For models no longer made, we use the last new price.
New cars
New cars use what Swedish dealers advertise them for. For each model we compare the price in ads for new cars in October 2026, mainly on Blocket, with the list price including VAT of the same version in the Swedish Tax Agency's new car price list of June 2026. The more ads there are, the more they weigh against the list price: with n ads the median of the ads gets the weight n/(n+4), so eight ads already count for two thirds. This applies to every version of the model. With fewer than three ads for new cars, we use the list price, and we never use more than the list price, since ads above it usually carry extra equipment. A used model year always costs at least 3 percent less than a new car and at least 2 percent less per year than a newer model year. The residual value is worked out from the ad prices, just as for used cars.
Fuel
Distance × real-world consumption × price. The default of 12,500 km per year is close to the Swedish average, which was 12,430 km in 2025 according to Trafikanalys. We convert the official consumption to real-world consumption. Petrol, diesel and hybrid cars use about 20 percent more than the WLTP figure according to European Commission data from the cars' own fuel consumption meters. For older cars with NEDC figures the gap is 9 to 40 percent depending on model year according to the ICCT. For electric cars we add 25 percent to WLTP, since winter and motorway driving use more. Plug-in hybrids use on average 3.5 times as much petrol as in the test according to the European Commission, because they are charged less often than the test assumes. We use 2.5 times as much petrol and 20 percent less electricity than the test, for a car charged at home.
Vehicle tax
Swedish vehicle tax, based on CO₂ emissions. For the first three years a malus applies: SEK 107 per gram between 75 and 125 g/km and SEK 132 per gram above 125 g/km, plus a base amount of SEK 360. After that, SEK 22 per gram above 111 g/km. Diesel cars pay a fuel surcharge (SEK 13.52 per gram) and an environmental surcharge (SEK 250). For diesel cars first registered before July 2018, the base amount and CO₂ amount are instead multiplied by 2.37, and the environmental surcharge is SEK 500 for cars from before 2008. Electric cars and plug-in hybrids pay SEK 360.
Insurance
Estimated comprehensive insurance per model. Pricier versions cost more to insure, and the premium drops as the car loses value.
Servicing and repairs
Servicing is an estimated yearly amount that rises 3 percent for each year the car gets older, up to 15 years of age. For Kia the amount is based on Kia's own service agreement prices (October 2026, kia.com). On top of that come expected repairs once the warranty has run out. First, the brand's average repair cost according to RepairPal, rising with the car's age at the same rate as the share of cars with faults in the TÜV Report. Second, known faults for that specific model and engine, mainly from BilKoll's buying guides, such as the timing belt on PureTech engines, DSG gearboxes and the angle gear on older all-wheel-drive Volvos. Each fault counts as the risk that it happens while you own the car times what the repair costs, spread out per month. The risks are our estimates. Electric cars get half as much in other repairs, since they break down less often according to the ADAC breakdown statistics, but we add the risk of charging faults and of the battery needing repair or replacement (see Battery ageing).
When does a car stop getting cheaper?

On average a car stops getting cheaper to own at about 11 years. From then on repairs and servicing (SEK 1,040 a month) cost more than the car loses in value (SEK 952), and the total cost barely moves, around SEK 3,198 a month and SEK 3,039 at 19 years: what you save on lower depreciation, the rising repairs eat up. So on average the car does not get more expensive per month, but it no longer gets cheaper either. Median of 136 models sold new, bought new and driven 12,500 km a year.

01,0002,0003,0004,0005,00015101519car age, years
  • Total per month
  • Depreciation
  • Servicing and repairs
Battery ageing
The battery in an electric car or plug-in hybrid loses capacity with age and mileage. By our calculation an electric car with a liquid-cooled battery has about 85 percent left after 8 years and 120,000 km. That matches the average of just under 2 percent a year in Geotab's measurements of more than 10,000 electric cars. Batteries without liquid cooling, as in the Nissan Leaf, VW e-Golf, Renault Zoe and Dacia Spring, age 1.3–1.7 times as fast. Tesla batteries and BYD's LFP batteries age a little more slowly. The range drops at the same rate as the capacity, and a worn battery uses a little more electricity. For a used car we show the estimated range today, both by WLTP and in real-world driving, where it is about 20 percent shorter. Older model years are calculated with the battery they had then, for example 22 or 41 kWh in an older Renault Zoe. The cost includes the risk that the battery needs repair or replacement once the battery warranty has run out. The warranty usually covers 8 years or 160,000 km and also covers capacity below about 70 percent. The risk of replacement rises when the capacity drops below 80 percent, and the risk of repair rises with age. A replacement costs about SEK 2,500 per kWh plus labour, so about SEK 110,000 for a 40 kWh Nissan Leaf. A plug-in hybrid with an older battery covers less of its driving on electricity and uses more petrol. The risks are our estimates.
Value grade
The A–E grade weighs the monthly cost against what you get. A car gets 0–5 points each for quality, design, comfort, luxury, safety, space and performance, so at most 35 points. The monthly cost gives one cost point for every 10 percent it is above SEK 1,500. What you get minus the cost points gives the grade, and A is the best value. Quality is based on reliability in the TÜV Report 2026 and the ADAC breakdown statistics 2025 where the model is included, otherwise on our estimate. It drops as the car gets older, since the share of cars with major defects at inspection rises from about 10 percent at 5 years to 33 percent at 15 years according to the TÜV Report. Safety is the Euro NCAP star rating (3 points if the car has not been tested), minus one point for cars from before 2016 and two points for cars from before 2010, which lack modern safety systems. Luxury is the same level as on the slider. Design and comfort are our judgement based on car reviews, and winners of World Car Design of the Year get top marks for design. Sporty versions get lower comfort but higher performance. Space is based on boot volume and performance on acceleration. The Best value sort follows the points.
Luxury and sportiness
Every version gets a luxury level and a sportiness level from 1 to 5. The luxury level is based on brand, model and trim level. Sportiness is based on acceleration, body type and brand, with a little extra for sporty versions such as GTI, AMG, M and RS. Extremely sporty in practice takes a real sports car or one of the very fastest versions, while hot hatches such as the Golf GTI and BMW M135 count as very sporty. When you choose a level, we show the cars that reach it and calculate with the cheapest version of each car that does. Cars that don't reach the level in any version aren't shown.
Fuel prices
Petrol and diesel are the big chains' list prices. The home-charging price is the SE3 spot price plus the retailer's margin, grid fee, energy tax and VAT. Prices update automatically once a day. You can enter your own prices under Change prices.
Lease or buy
For cars that are commonly leased privately in Sweden we compare the brand's own private lease offer with buying the same version new and selling it when the lease ends, usually after 36 months. Leasing: the payment at your distance (the brand's price for more distance where given, otherwise an estimate), set-up and invoice fees and any higher first payment spread per month, and servicing if it isn't included. Buying: the depreciation from the list price of the same version (or the ad price for new cars, if lower) to the residual value in ads, interest on the money (5 percent unless you change it) and servicing. The residual value is adjusted by 2 percent per 10,000 km you drive more or less than the model typically covers over the same years; that is how much ad prices for the same model and model year differed in October 2026. Beyond the oldest model year in the ads, the curve is extended with at least 8 percent depreciation a year, since older cars in the ads lose 35–40 percent over four years. Fuel and tax are the same, and so is insurance unless the leasing company requires its own, like Peugeot. The offers were read on the brands' websites on 26–27 October 2026 and may have changed since.
Images
The photos show the right model and generation and come from Wikimedia Commons, where they are freely licensed. The photographer and licence are shown on the image when you open a model. Trim, colour and model year can differ from the version in the calculation. Where there is no free photo, a computer-generated image is shown.

Updated 2026-10-29