Debt Repayment Calculator

Find your debt-free date, see the true cost of your balance, and discover how extra monthly payments can change everything.

Monthly compounding · Extra payment impact · Canada & USA

Debt Repayment

Loan Details

$
%
$

Optional — e.g. credit card annual fee

$
$

Optional — see the impact below

Debt-Free Date

September 2030

50 months to payoff

Monthly Payment$150.00
Goes to interest
$83.29
Reduces balance
$66.71
Total Interest Paid$2,357
Total Cost$7,357

See how extra payments could shorten your payoff.

Cost breakdown

Debt Breakdown

$7,357total cost
Principal Balance
68%$5,000
Estimated Interest
32%$2,357
Total Cost$7,357

Balance over time

Payoff Timeline

Current pace
With extra $100/mo

FinCalc Smart AI Debt Analysis

Debt Payoff Status
47% interest
Watch

50 mo to payoff

Your 50-month payoff is manageable. A modest increase in monthly payment can noticeably reduce your total interest cost.

Smart Opportunity Found
$1,225

estimated interest saved

by adding $100/month to your payment

$100.00/mo
Extra payment
25 mo
Earlier payoff

Enter a custom amount in the Extra Payment field above ↑

Interest Pressure

In month one, $83.29 of your $150.00 payment goes to interest — only $66.71 reduces your balance. This front-loading is why early repayment feels slow.

Payment Efficiency

Only 44% of each payment currently reduces your balance. More than half of every dollar is lost to interest. Extra payments flip this ratio faster than any other action.

Next Best Step

Adding $100/month saves $1,225 and cuts 25 months from your timeline. Use the Extra Payment field above to model your exact number.

Disclaimer: This analysis is for illustrative purposes only and does not constitute financial, tax, or investment advice. Results assume a fixed interest rate, no new charges to the balance, and consistent monthly payments. Individual outcomes will vary based on lender terms and personal circumstances. Consult a licensed financial advisor before making financial decisions.

How It Works

The Payoff Formula

To find how many months it takes to pay off a balance, we invert the standard amortisation formula and solve for n (number of payments):

n = −ln(1 − r × P ÷ M) ÷ ln(1 + r)
VariableMeaning
nNumber of monthly payments until the balance reaches zero
PCurrent outstanding balance
MMonthly payment (must be greater than the monthly interest charge)
rMonthly interest rate = annual rate ÷ 12 ÷ 100

The calculator runs this formula as a month-by-month simulation so the final (partial) payment is handled correctly and total interest is exact rather than approximated.

Why Interest Front-Loads

Each month, interest is calculated on the current outstanding balance — not the original balance. When the balance is large, the interest charge is large, leaving very little of each payment to reduce principal.

For a $5,000 balance at 19.99%, the first payment of $150 includes approximately $83 in interest and only $67 toward the balance. As the balance falls, the interest charge shrinks and an increasing share of each payment reduces principal — but the process accelerates slowly unless payment size increases.

How Extra Payments Work

Any amount paid above the interest charge reduces the principal directly. A smaller principal means less interest next month — which means more of the next payment reduces principal, and so on. This compounding effect means even a modest extra payment has a disproportionately large impact on total interest and payoff time.

The calculator always shows what adding $100/month would save compared to your current payment, regardless of whether you have entered an extra payment amount. You can also enter your own extra payment to see its precise effect.

Monthly Compounding — Canada and USA

Personal debt — credit cards, personal loans, lines of credit — compounds monthly in both Canada and the USA. The monthly rate is simply:

r_monthly = annual_rate ÷ 1200

This differs from Canadian mortgages, which are required by the Interest Act (RSC 1985) to compound semi-annually. That rule does not apply to consumer credit products. The formula used in this calculator is correct for both countries.

Assumptions

  • Fixed rate — the annual interest rate does not change over the repayment period. If your rate is variable or a promotional rate expires, your actual payoff date will differ.
  • Static balance — no new charges are added after repayment begins. The calculator models a closed balance being paid down.
  • Consistent monthly payments — payments are made on the same day each month with no missed or late payments.
  • Final partial payment — the last payment is the exact amount required to clear the remaining balance, which will be less than your regular payment amount.

Frequently Asked Questions

This calculator is for illustrative and informational purposes only. Results are estimates and may not reflect actual credit card terms, loan agreements, fees, interest changes, minimum payment rules, or lender conditions. This does not constitute financial, tax, or legal advice. Consult a licensed financial advisor or qualified professional before making financial decisions.