What the calculator shows
Enter the balance, applicable annual rate and a fixed monthly payment. The result shows the number of months, total interest and total paid, and warns when the payment does not reduce the opening balance.
Calculation method
Each month adds balance multiplied by the annual rate divided by 12, then subtracts the fixed payment. The last payment falls to the remaining amount due. The model assumes no new purchases, cash advances, fees or rate changes.
Inputs to confirm
Use the rate applying to the balance on your statement. Issuers may use daily interest and different minimum formulas; confirm promotional expiry dates, transfer fees and minimum payments in the card agreement.
Worked zero-rate boundary example
A CA$1,200 balance at 0% with a CA$100 fixed monthly payment takes exactly 12 months and no interest. At a positive statement rate, interest is added before each payment; if CA$100 no longer reduces the balance, the calculator refuses a payoff date.
| Change | Immediate effect | Check |
|---|---|---|
| Higher annual rate | More monthly interest | Statement rate table |
| Higher fixed payment | Faster principal reduction | Monthly budget |
| New purchases | Not modeled | Run a separate balance scenario |
Start with the rate applying to the actual balance
A Canadian card statement can contain purchases, cash advances, transfers and promotions at different rates. This tool deliberately models one balance and one entered rate.
The payment must exceed monthly interest
Interest is added before the fixed payment. If the payment cannot reduce the opening balance, the calculator refuses to produce a misleading payoff date.
Monthly interest is a planning approximation
Issuers commonly use daily balance methods and statement-cycle dates. The model divides the entered annual rate by 12, so use it to compare payment scenarios rather than reproduce a statement to the cent.
Run separate scenarios for separate balance types
Promotional expiry, cash-advance rates, transfer fees, penalty pricing and new purchases can change the path. Use the statement rate table and cardholder agreement before choosing the input.
Primary sources
Financial Consumer Agency of Canada — credit card payment calculator