Car Total Cost of Ownership
Car Cost of Ownership Calculator — True 7-Year Cost
What this calculator does
This calculator shows the full cost of car ownership over a number of years. It includes purchase price, depreciation, gas, insurance, and maintenance.
The math, with a worked example
Yearly gas = miles per year ÷ MPG × gas price. Insurance and maintenance are entered monthly, so each is multiplied by 12. Value left after N years = purchase price × (1 − annual depreciation rate) to the power of N, and the depreciation charge is what that erased, spread evenly across the years. Yearly cost = gas + insurance + maintenance + depreciation. A $25,000 car driven 12,000 miles a year at 28 MPG on $3.50 gas, with $120 monthly insurance and $75 monthly maintenance, runs about $6,267 a year, or $43,866 across 7 years. Depreciation is the biggest slice: at 15% a year the car is worth roughly $8,014 at the end.
Why this matters
The sticker is the smallest number in car ownership. Gas, insurance, maintenance, and above all depreciation roughly double it: a $25,000 car runs about $43,866 over 7 years in the worked example. The per-year figure, not the price, decides whether a car fits your budget.
Methodology and transparency
Yearly cost = gas (miles ÷ MPG × price) + 12 × monthly insurance + 12 × monthly maintenance + depreciation, where depreciation applies a constant annual percentage to remaining value and spreads the loss evenly across your ownership years. That constant-rate assumption is the one most likely to be wrong: real cars fall fastest in years 1–2 and slower later, so short ownership windows understate the hit and long ones overstate it, and maintenance climbs with age while the input stays flat. Everything runs in your browser; no data is sent or stored.
Last reviewed: 2026-08-08
Common questions
Is depreciation really that important?
Yes. New cars can lose 15–25% of value per year, making it the biggest ownership cost.
Should I buy new or used?
Used cars usually have lower depreciation and insurance costs. Run the numbers for both.
How do I reduce ownership cost?
Buy a fuel-efficient, reliable used car, drive fewer miles, and maintain it regularly.