Estimate how long it could take to clear a debt, the total interest payable and the effect of making an extra monthly payment.
This is an estimate using a fixed interest rate and one payment per month. Actual lender calculations, fees, rate changes and payment dates can change the result.
How to use the Debt Payoff Calculator
Enter your current balance, annual interest rate and planned regular monthly payment. Add an optional extra payment to see whether paying more could shorten the repayment period and reduce interest.
How the debt payoff estimate works
The calculator applies one month of interest to the remaining balance, subtracts the chosen payment and repeats the process until the balance reaches zero. The final payment is limited to the amount still owed.
| Output | Method |
|---|---|
| Monthly interest | Remaining balance × APR ÷ 12 |
| New balance | Balance + monthly interest − payment |
| Total interest | Sum of all monthly interest charges |
| Interest saved | Regular-payment interest − extra-payment interest |
Why paying more than the minimum matters
A minimum payment may cover interest while reducing only a small part of the balance. MoneyHelper explains that paying only the minimum can make a small impact on the amount owed. Its guide to reducing borrowing on credit provides further guidance.
Check that the payment is affordable
Higher payments can reduce repayment time, but essential bills and priority debts come first. Use realistic figures and keep an emergency buffer where possible. If the payment does not cover the first month’s interest, this calculator warns that the balance would not reduce under the stated assumptions.
Related calculators
Compare a fixed borrowing schedule with the Loan Repayment Calculator UK. Review available monthly cash with the Budget Calculator UK. For a separate growth or borrowing calculation, use the Interest Calculator. Browse more tools on the United Kingdom Calculator homepage.
Frequently asked questions
Does this calculator use simple or compound interest?
It applies interest monthly to the remaining balance, which models a reducing-balance debt with monthly compounding.
What happens if my payment is too low?
If the payment does not exceed the first month’s interest, the balance will not reduce under these assumptions and the calculator shows a warning.
Does the result include late fees?
No. Add lender fees to the starting balance only when that treatment matches your agreement, or calculate them separately.
Can I use a zero interest rate?
Yes. Enter 0 for the APR and the calculator will divide the balance by the monthly payment without adding interest.
Will an extra payment always save interest?
With a positive fixed rate and no penalty, paying more normally clears the balance sooner and reduces interest. Check your credit agreement for any charges or restrictions.