Cost per mile turns a jumble of annual vehicle expenses — a gas receipt here, an insurance bill there, a depreciating trade-in value — into one comparable number. It's the figure that lets you fairly compare a cheap-to-buy gas guzzler against an expensive-to-buy fuel sipper, or decide whether driving your own car for a side gig actually pays after expenses.
How the Cost Per Mile Calculator works
The calculator adds five annual cost categories — fuel, maintenance, insurance, depreciation, and other costs — into a single total, then divides by your annual miles driven. That division is the whole formula; there's no hidden adjustment or regional multiplier. The IRS standard mileage rate shown alongside your result (72.5¢/mile for 2026 business use) is a nationally averaged benchmark the IRS itself calculates from fixed and variable costs across a large vehicle sample — it's a useful comparison point, not a target your own number needs to match.
Inputs and what they mean
Annual miles driven is the denominator for every result on this page — get it right and everything else follows. Fuel and maintenance are usually the easiest to estimate from receipts or a service history. Insurance is your annual premium. Depreciation is the hardest to pin down exactly: a rough estimate is last year's resale value minus this year's, or you can run the numbers through Calculover's Car Depreciation calculator first. Other costs is a catch-all for registration fees, parking, tolls, and loan interest — anything real that doesn't fit the first four buckets.
Limits and edge cases
If annual miles is zero, cost per mile is undefined — the calculator shows a partial result rather than a divide-by-zero error, and you'll need to enter a positive mileage figure to see a number. The fuel-only view on the Fuel Only tab deliberately excludes maintenance, insurance, and depreciation, so don't use it as a stand-in for total cost of ownership — it will understate your real cost, often significantly. And because depreciation varies enormously by make, model, age, and market conditions, a rough depreciation estimate can swing your total cost per mile more than any other single input; if you want a firmer number, look up your specific vehicle's typical resale curve rather than guessing.