Total Debt Interest Calculator
Add up the estimated annual interest cost across up to three separate debts to see your total interest burden at current balances and rates.
Your results
Calculation breakdown
- Annual interest per debt
- balance × rate
- Weighted average rate
- total interest ÷ total balance
Worked example
A $4,000 card at 20% and a $12,000 loan at 9% together cost about $1,880 a year in interest, a weighted average rate of just under 12% across the $16,000 owed.
Assumptions
- Estimates interest at current balances and rates over one year, ignoring repayments reducing the balance.
- Leave any unused debt slot at zero.
- Rates and balances should reflect your latest statements for accuracy.
How this calculator works
This calculator lets you enter the balance and interest rate for up to three separate debts, such as a credit card, personal loan and car loan, and totals the estimated annual interest across all of them. It is a quick way to see your overall interest burden before deciding whether consolidation or a payoff strategy would help.
Frequently asked questions
Why look at total interest across all debts?
Seeing the combined annual interest cost highlights how much of your money goes purely to interest each year, which can motivate prioritising higher-rate debts first.
Does this calculator include repayments?
No, it estimates interest at the current balance and rate for a year; use the debt avalanche or early loan repayment calculators to model paying the debts down over time.
What should I do if my total interest looks high?
Consider the debt avalanche method, debt consolidation, or negotiating a lower rate with your provider, then compare the options using the related calculators.
Results are estimates only and are not financial, tax, legal or credit advice.