What this calculator adds up
Most people think of their car as a monthly payment plus gas. This calculator adds up everything it really costs:
- Depreciation: what you paid minus what you’ll get when you sell.
- Gas, from your miles, mpg and the price per gallon.
- Insurance, registration and maintenance, per year.
- Parking, per month, and the total interest on your loan if you have one.
It shows the cost per month, per year, per mile and over the whole time you own the car, and which item takes the biggest share.
Example: a $35,000 new car
Kept for six years and then sold for $15,000, driven 12,000 miles a year at 30 mpg with gas at $3.20:
| Cost | Per year |
|---|---|
| Depreciation ($20,000 over 6 years) | $3,333 |
| Insurance | $1,800 |
| Gas (400 gallons) | $1,280 |
| Maintenance and repairs | $900 |
| Registration and fees | $150 |
| Total | $7,463 |
That’s about $622 a month, 62 cents a mile and $44,780 over the six years, and that’s without a car loan or paid parking. Depreciation alone is 45% of the total, more than gas and maintenance combined.
Why driving less makes each mile more expensive
Most of these costs are fixed: the car loses value and needs insurance whether you drive it or not. Drive the same car only 6,000 miles a year and the monthly cost barely drops, to about $569, but each mile costs $1.14 instead of 62 cents. If you drive very little, that’s worth comparing with ride-hailing or car sharing.
New vs. used
A new car loses value fastest in its first years, and the buyer of a used car skips that part. A $20,000 used car that’s worth $11,000 six years later depreciates $1,500 a year instead of $3,333. Even budgeting $1,200 a year for maintenance, the total comes to about $494 a month.
Filling in the numbers
- Resale value: look up what similar cars, a few years older, sell for on used car sites or valuation guides.
- Insurance: use your actual premium. It varies a lot with your state, your age and your driving record.
- Registration and fees: some states also charge an annual property tax on vehicles; include it here.
- Loan interest: the total interest over the whole loan, not the monthly payment. The payment itself is mostly the car’s price, which is already counted through depreciation.
To work out the gas for a specific trip, use the gas cost calculator.