CarvicoAsk most drivers what their car costs to run and you will hear a fuel figure. It is the only cost with a receipt attached to every single use, so it is the one the brain files under "cost of driving." Meanwhile the vehicle is losing value in the driveway, the insurance renews, and the 60,000-mile service arrives — none of which feel like they happened because you drove somewhere.
The five components
| Component | How to measure it | Behaves like |
|---|---|---|
| Depreciation | Purchase price minus what it is worth today, over the miles driven since purchase. | Mostly time-based on newer cars, mileage-based on older ones. Usually the biggest number. |
| Fuel or charging | Total spend at the pump ÷ miles driven. This is exactly what a fuel log gives you. | Purely per-mile. |
| Maintenance & repairs | Every service, part, and shop visit ÷ miles over the same window. Include tires. | Per-mile, but lumpy — averages need years, not months. |
| Insurance | Annual premium ÷ annual miles. | Fixed. Drive more and the per-mile figure falls. |
| Registration, taxes, inspection | Annual total ÷ annual miles. | Fixed, small, easy to forget. |
Two items deliberately left out: finance interest (include it if you have a loan — it is real money) and parking or tolls (include them if they are routine for your driving). The framework matters less than being consistent about it year to year.
The depreciation shortcut
You do not need a valuation service. Look up your exact year, trim and mileage on any major listing site, take the middle of the private-party range, and subtract it from what you paid. That is your depreciation to date, accurate enough for every decision on this page. Repeat annually — the trend is more informative than the number.
Cost-per-mile calculator
Your car, your numbers
Runs entirely in your browser — nothing is uploaded, and this page carries no analytics or trackers. Use a 12-month window if you have one; otherwise use the whole time you have owned the car and set the period accordingly.
Running cost is fuel plus maintenance — what an extra mile costs you today. Total cost adds insurance, registration and depreciation — what the car costs you to have at all. Both are true; they answer different questions.
What the national numbers say
For a sanity check rather than a target: AAA's Your Driving Costs study for 2025 put the average cost of owning and operating a new vehicle at $11,577 per year, on an assumption of 15,000 miles annually across five years of ownership — about 77 cents per mile all in. Fuel was a modest slice of that, averaging roughly 13 cents per mile. The study covers new vehicles bought and held for five years, which is precisely the ownership pattern where depreciation is at its most brutal.
Most people reading this are not in that case. The two big divergences:
- Older, paid-off car. Depreciation per mile collapses — a ten-year-old commuter car loses very little value per year. Maintenance rises but rarely enough to compensate. Total cost per mile commonly lands well under half the new-car figure.
- Low annual mileage. The fixed costs — insurance, registration, time-based depreciation — spread over fewer miles, so cost per mile rises sharply. At 4,000 miles a year, a car can cost more than a dollar a mile while feeling cheap because you barely buy fuel.
Why your own number beats any average
National averages price a hypothetical car in a hypothetical climate with a hypothetical shop rate. Your log prices your car: your commute, your winter, your mechanic, your habit of deferring the transmission service. Once you have twelve months of fuel and service entries, the calculation above takes about a minute — and it is the only version of this number worth acting on.
Marginal vs total: the distinction that changes decisions
People routinely use the wrong one and reach the wrong conclusion.
| Question | Use | Because |
|---|---|---|
| "Is it cheaper to drive or fly to my parents'?" | Running cost | Insurance and depreciation happen either way. Only fuel and wear are caused by the trip. |
| "Should we keep the second car?" | Total cost | Selling it removes insurance, registration and future depreciation as well as fuel. |
| "Repair the old car or buy a newer one?" | Total cost, both cars | A $2,400 repair looks enormous until you price a year of depreciation on the replacement. |
| "What should I charge a client for mileage?" | Total cost, or the IRS rate | You are being compensated for providing the vehicle, not just for the fuel. |
The repair-or-replace case is the one where good records pay for themselves outright. "This car has cost me $0.41 a mile over four years, including two bad repairs" is a decision. "It feels like it's always in the shop" is a mood.
Four decisions this number answers
- Whether the repair is worth it. Compare the repair, spread over the miles you expect to get from it, against the per-mile cost of the car that would replace it. A $2,000 repair that buys 40,000 more miles is 5 cents a mile — usually the cheapest transportation available.
- What the "cheap" car really cost. Purchase price is one line in a five-line problem. Cheap cars with expensive fluids and short service intervals routinely lose to boring ones on a per-mile basis.
- Whether the EV math works for you. Charging cost per mile is straightforward to log; the real comparison needs maintenance and depreciation over the same window, and both differ from the gasoline case in ways that only your own numbers settle.
- What to ask when you sell. A documented per-mile cost, with the service history behind it, is a persuasive artefact for a buyer — and the reason records move price.
Where the inputs come from
The calculation is easy. Having the inputs is the whole problem — and it is why a fuel and service log is a financial tool, not a hobby:
- Fuel spend and miles: straight from a fuel log, where every entry already carries a cost and an odometer reading.
- Maintenance and repairs: from a service log, where each entry carries a cost, a date and a mileage. Without one, you are reconstructing four years from a shoebox of receipts and a credit-card statement that says AUTO PARTS.
- Insurance and registration: annual, easy to look up once a year.
- Value: one listing-site lookup a year.
If you are starting from nothing, start today rather than trying to reconstruct the past. Twelve months from now you will have a real number; the alternative is having the same argument with yourself again next July.
Questions
Should I include the car payment?
Include the interest portion as a cost; the principal is not a cost, it is a transfer into equity, and counting both it and depreciation double-counts. If you want a cash-flow view instead of an economic one, that is a separate, equally valid calculation — just keep them separate.
How do I handle tires?
As maintenance, but ideally amortised: a $900 set expected to last 45,000 miles is 2 cents a mile. Charging it all to the month you bought them makes that month look like a catastrophe and the following year look free.
What about an EV's charging costs?
Log kWh and cost per session exactly as you would fuel. Home charging at off-peak rates and DC fast charging on a road trip can differ by a factor of three or four per mile, so an average that mixes them is only meaningful if your mix stays stable.
Does this work for a motorcycle, RV, or boat?
Yes — the framework is unit-agnostic. Anything with an odometer or hour meter, fuel, and maintenance fits. Cost per hour is the usual denominator for boats.
Your cost per mile, calculated as you log
Carvico computes cost per mile from your own fuel and service entries — no spreadsheet, no reconstruction. Receipt scanning fills the entries in; the data stays on your iPhone and your own iCloud.
Download on theApp StoreSources
- AAA, Your Driving Costs (2025 edition) — annual cost of new-vehicle ownership and per-mile fuel figures. newsroom.aaa.com
- AAA Automotive, Your Driving Costs methodology overview. aaa.com