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Tools Credit card interest calculator

Credit card interest calculator

Enter the figures from your statement. See what paying in full, paying part, or paying only the minimum would cost, in estimates you can check.

Runs only in this browser tab. Nothing is sent or saved, and it never asks for a card number. Example figures are filled in; replace them with the ones on your statement.

Your statement

The new balance on the statement, in dollars.

The annual rate for purchases, shown on the statement.

The last day of the statement period.

Your payment

Also used as the fixed monthly payment in the payoff comparison.

Optional: minimum payment rule and new spending

Rules vary by issuer; your statement and agreement show yours. The FCAC describes two common formulas: the higher of a dollar amount (typically $10) or a percentage of the balance (typically 3%), or a flat amount (usually $10) plus interest and fees. Its sample information box uses 2% or $10. Since August 1, 2025, the minimum for Quebec residents is 5%.

Used only in the payoff comparison. While a balance is carried, new purchases are assumed to accrue interest too.

Estimates

  1. Pay the full balance by the due date

    $0.00 interest

  2. Pay your planned amount instead

    —

  3. Minimum payments only, or your fixed payment

    —

    Payoff, estimated
    MeasureMinimum onlyYour fixed payment

  4. Days left until the due date

    —

  5. Cash advances and balance transfers

    Cash advances and cash-like transactions, such as wire transfers, money orders and gambling transactions, have no interest-free grace period: interest runs from the day of the transaction, usually at a higher rate, and a fee often applies. Balance transfers generally get no grace period either; a promotional rate, if offered, lasts only for the period in its terms.

Independent education, not financial advice. Estimates only; your card agreement governs.

How these are estimated: interest = average daily balance × APR ÷ 365 × days, with the payment made on the due date (or today, if that has passed) and a statement period running to the same date next month. No fees, no rate changes, no cash advances. Issuers differ in how they round, which day interest starts, and how payments are applied, so your statement may show a different figure.

Sources

Rules and examples checked against these sources on October 31, 2026.

  1. FCAC: How credit cards work (grace period, cash advances, balance transfers)
  2. FCAC: Paying off your credit card (minimum payment formulas, interest from the purchase date)
  3. Bank Act, s. 627.34: statement, 21-day minimum before the due date, no interest if paid in full (Justice Laws)
  4. Credit Business Practices Regulations (SOR/2009-257), s. 3: the same rules for federal trust and loan companies, retail associations and insurers (Justice Laws)
  5. Financial Consumer Protection Framework Regulations, s. 60: what a credit card information box must show (Justice Laws)
  6. FCAC: Example information box, credit agreement for a credit card
  7. FCAC: Credit Card Payment Calculator (the government's own payoff tool)

How the grace period works

  • The statement closes, the clock starts. Purchases build up over a statement period of about a month. The grace period runs from the end of that period to the payment due date.
  • At least 21 days at federally regulated issuers. For banks, section 627.34 of the Bank Act says the minimum payment can't be due less than 21 days after the billing cycle ends, and that no interest may be charged on that cycle's purchases if the balance is paid in full by the due date. The same rules apply to federal trust and loan companies, retail associations and insurers under the Credit Business Practices Regulations. Credit unions and other provincially regulated issuers follow provincial rules and their own agreements, which may differ.
  • A due date on a weekend or holiday moves to the next business day for federally regulated issuers.
  • Only purchases get the grace period. Cash advances, cash-like transactions and balance transfers are charged interest from the day they happen.

How the interest is calculated

  • Pay anything less than the full balance and the grace period stops protecting those purchases. The FCAC explains that you then pay interest from the date you made each purchase, and keep paying it until the balance is paid in full.
  • The daily method. Most information boxes say interest is calculated on the average daily balance and charged monthly. In plain terms: add up each day's balance, divide by the number of days, then multiply by the annual rate ÷ 365 × the days in the period. At 20.99%, a $1,000 balance costs about 57.5 cents a day.
  • The minimum payment is designed to be small. A large share of it goes to interest, and as the balance falls, so does the minimum. Federally regulated issuers must show on each statement how long repayment would take at the minimum alone.
  • Read your own terms in the information box. It must state the grace period, how interest is determined, the minimum payment formula and the fees. The FCAC publishes an example.

For the longer version, with worked examples, read the note How credit cards work: grace periods, interest and minimum payments. The FCAC's Credit Card Payment Calculator is a useful second opinion on payoff times.