Total Debt Cost Calculator
Full lifetime cost of all your debts combined.
Calculate total lifetime cost of all debts including all interest. See true cost of borrowing. Enter debt 1 monthly to see total amount paid across all.
What this tool does
Enter debt 1, 2, 3 monthly payments and remaining months. The tool calculates total amount paid across all.
Enter Values
Formula Used
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Disclaimer
Results are estimates for educational purposes only. They do not constitute financial advice. Consult a qualified professional before making financial decisions.
True debt cost is total amount paid over the loan lifetime, not just balance. 15k debts at average 350/month for 60 months = 21k total — 6k pure interest.
Run it with sensible defaults
Using debt 1 monthly of 200, debt 1 months remaining of 36, debt 2 monthly of 100, debt 2 months remaining of 24, the calculation works out to 10,200.00. Nudge the inputs toward your own situation and the output recalculates instantly. The defaults are meant as a starting point, not a recommendation.
The levers in this calculation
The inputs — Debt 1 Monthly, Debt 1 Months Remaining, Debt 2 Monthly, Debt 2 Months Remaining, and Debt 3 Monthly — do not pull with equal force. Frequency and unit price pull the total in different directions. The biggest surprise for most people is how small recurring amounts compound into large annual figures — that's where this calculation earns its keep.
How the math works
Sum of (monthly × months) across all debts. The working is transparent — you can verify every step yourself in the formula section below. No black box, no opaque "proprietary model".
Using this to stay on track
The most common failure mode isn't the plan itself — it's letting the balance creep back up while you're paying it down. Set a rule: no new debt added to the same account until the balance is zero. The calculator is only useful if the number it shows doesn't keep resetting.
What this doesn't capture
Real payoff journeys include missed payments, fee changes, balance transfers, and promotional rates that reset. The calculation assumes a steady plan; reality is rarely that clean. Use the figure as the best-case plan against which actual progress gets measured.
Total debt produces lifetime cost based on the inputs provided.
Inputs
This example uses typical values for illustration. Adjust the inputs above to match a specific situation and see how the result changes.
Sources & Methodology
Methodology
Sum of (monthly × months) across all debts.
References
Frequently Asked Questions
Why does this matter?
Does this show interest separately?
Which debt to pay first?
What about minimum payments?
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