Car Affordability Calculator
Your car costs more than the monthly payment. See the real number — including depreciation, insurance, fuel, and maintenance.
How to Use This Calculator
True Monthly Cost tab
The default tab. Enter the car price, insurance, and fuel cost. The calculator adds loan payments, depreciation, and maintenance to show the real monthly cost of owning. Expand "More options" to adjust down payment, loan rate, term, maintenance, depreciation rate, and parking.
Car vs Alternatives tab
Enter the same car details, plus your public transit pass cost and rideshare budget. The calculator compares total car ownership cost against transit + rideshare, showing monthly and 5-year savings. It also shows what those savings would grow to if invested.
Share your result
Every input is encoded in the URL. Click Share, send the link to your partner — they'll see your exact numbers. Perfect for the "do we really need a second car?" conversation.
The Formula
True monthly cost includes every expense category, not just the loan payment:
Most people underestimate car costs because they only think about the loan payment. But depreciation alone can exceed the payment — a $35,000 new car losing 15%/year depreciates $437/month in invisible value loss.
The Car vs Alternatives tab adds an investment growth projection: savings from going car-free, compounded at 8%/year over 5 years.
Example
Alex — Chicago, IL
Alex is considering buying a $35,000 car. He currently uses the CTA ($105/month) and Uber for weekend trips ($250/month).
True Monthly Cost tab
The loan payment is $691, but the true cost is $1,508/month — more than double. Depreciation is the hidden killer: $437/month in value loss that never shows up on a bill.
Car vs Alternatives tab
Alex saves $1,153/month without a car. Over 5 years, invested at 8%, that's $85,200. He decided to skip the car and budget $400/month for rideshare instead — still saving $1,100/month.