Credit Card Calculator

Calculate Credit Card Interest

This credit card calculator estimates the cost of repaying an entered balance. It compares declining minimum repayments with a fixed monthly payment and a fixed payment plus extra. The balance-transfer scenario shows what happens when the promotional rate ends.

Daily interest is the interest-bearing balance multiplied by the annual rate divided by 365. At the example's $5,000 balance and 20% annual rate, that is $2.74 a day. A 30-day cycle adds an estimated $82 in interest before the payment.

An annual percentage rate (APR) is a yearly rate, not the interest charged each month. For an unchanged balance, multiply daily interest by the cycle's days. An annual rate divided by 12 gives an average monthly rate, while a 28-day or 31-day statement produces a different charge.

The model keeps each balance unchanged within a cycle, adds interest at cycle end and then applies the payment. Unpaid posted interest enters the following cycle's interest-bearing balance. Payments during an actual statement cycle change its daily balances and therefore its interest.

CommBank's interest explanation describes separate calculations for purchases, cash advances and balance transfers. It also explains how purchase interest-free periods depend on the account's repayment history. This model assumes the entered purchase balance already bears interest.

Compare Minimum and Extra Repayments

The minimum-only scenario recalculates the repayment as the balance falls. With Percentage of closing balance selected, it applies your percentage after adding the cycle's interest and fee. It then uses the larger of that amount and your dollar floor, capped at the total owed.

Percentage plus charges instead adds all current-cycle interest and fees to a percentage of the opening balance. Percentage rounding can round that calculated amount up or down to whole dollars before applying the floor. These editable assumptions let you distinguish different statement rules.

Fixed payment holds your entered payment constant, while Extra payments adds the same extra amount each cycle. The target-term result calculates the smallest cent-denominated fixed payment that clears the original card within your chosen number of payments. The final payment can be smaller.

A payment below interest and recurring fees increases the debt. A payment equal to those charges leaves the debt unchanged. A reducing balance that still remains after 1,200 payments also has no displayed payoff or lifetime total.

The tool flags any fixed payment below its modelled minimum. That schedule describes the maths of the entered payment, not permission to underpay the account. Select Other account rules if an instalment plan or another arrangement cannot be represented by these settings.

Test a Balance Transfer

The balance-transfer comparison moves the full purchase and cash-advance debt, including an entered cash fee, to the new card. The transfer fee combines the percentage charge and any extra flat charge. The fee is financed in the transferred balance and counted once in total fees.

The promotional rate applies for the entered number of complete cycles. Any transferred balance remaining after the final promotional payment uses the revert rate from the next cycle. The result shows that remaining transferred balance separately from new purchases.

New purchases are added once at the start of both comparisons. On the new card, they use New-card purchase rate, even while the transferred debt has a promotional rate. Neither scenario includes repeated future spending.

Moneysmart's balance-transfer guidance explains transfer fees, introductory periods and the higher rate that can follow them. Compare the total payments as well as the promotional rate. A negative total saving means the entered transfer costs more.

Add Cash Advances and Card Fees

A cash advance has its own balance and annual rate. Its one-off fee is the greater of the entered percentage and dollar minimum. The model adds that fee to the cash balance before calculating interest.

Cash interest days sets how long the advance bears interest in the first cycle. Later cycles use Days per cycle. Use the full cycle for an advance already outstanding, or fewer days when modelling an advance part-way through the cycle.

For existing cash debt, enter the balance and set both cash-fee fields to zero if that fee is already included. This avoids adding it twice. The transfer comparison assumes the cash debt is transferred immediately, so it attracts the transfer rate instead of further cash-advance interest.

Current monthly fee and New monthly card fee apply to each active cycle on their respective cards. They are posted after that cycle's interest and enter the purchase balance for the next cycle. Annual fees need their actual timing modelled separately if dividing them across cycles would change the decision.

Highest rate first sends each payment to the highest-rate balance, then the next highest. Lowest rate first reverses that assumption. Equal-rate balances use purchase, cash and transfer order.

CommBank's payment-allocation explanation describes highest-rate allocation and separate treatment for instalment plans. ANZ also distinguishes statemented debt from later debits. Use Other account rules when those timing or plan rules materially change the comparison.

Use ANZ, CommBank and Moneysmart Inputs

Start with your statement's closing balance, then separate purchase and cash debt so the same dollars are not entered twice. Copy the annual rate for each balance and the minimum-payment rule from your account's terms. The minimum amount printed on one statement is not necessarily a constant payment for future months.

ANZ's credit-card conditions explain daily interest, statement balances and payment allocation. The letter of offer and promotional-plan terms also form part of the account's contract. Instalment amounts and overdue or over-limit debt can change what must be paid.

CommBank's statement guide identifies the account summary, payment summary and itemised interest and fees. Its minimum-payment warning compares minimum payments with a higher payment over two years.

ANZ's standard percentage calculation rounds up to whole dollars. CommBank's minimum-payment guide describes rounding down for its standard calculation. Their exceptions include different card types, instalment plans and over-limit amounts.

CommBank's card-change notice sets out changes to minimum payments for affected accounts. Use the percentage that applies to your statement rather than assuming all CommBank cards, or ANZ and CommBank cards, share one rule.

For a Moneysmart credit-card calculator comparison, use the same balance, annual rate, minimum percentage and dollar floor. Set cash advances, new purchases and fees to zero to match its stated scope. Keep the higher repayment fixed as the balance falls.

Daily-cycle timing and rounding must also agree before expecting identical results from two calculators. This page needs no lender login or account connection. Its inputs and downloaded schedule are processed on your device.

A Card Payoff Comparison

The fictional starting example has a $5,000 purchase balance at 20% annually. It repeats 30-day cycles, charges no card fees and makes payments at cycle end. Minimum repayments use 2.5% of the closing balance with a $25 floor and no whole-dollar rounding.

The extra $50 clears the original card eight payments sooner and saves $380 in interest. The target-term result is $253.82 per cycle to clear it within 24 payments. These comparisons retain the same starting debt and interest assumptions.

The separate transfer example charges a 2% fee, giving a starting transfer balance of $5,100. Twelve $200 payments at 0% leave $2,700 when the promotion ends. The following cycles use a 22% annual revert rate.

The transfer clears after 28 payments, including a final payment of $123.73. Total payments of $5,524 comprise $5,000 of original debt, a $100 transfer fee and $424 of interest. It saves $969 against keeping the original card at $200 per cycle.

Calculations retain precision between payments. Exact repayments and schedule rows show cents, while estimated interest totals and costs show whole dollars. Statement-level rounding can produce small differences.

What the Estimate Does Not Decide

The payoff estimate assumes equal statement cycles and a payment immediately after each cycle's charges. Actual payment receipt dates, changing rates and transactions within a cycle alter the daily balances. Purchase interest-free eligibility and residual interest also depend on the account's history.

The model treats posted interest and fees as interest-bearing in later cycles. It omits late fees, over-limit rules and instalment plans unless their effect is represented by your inputs. Select Other account rules when the model would otherwise imply an unsupported payoff.

A debt payoff calculation does not establish an approved credit limit or a lender's serviceability allowance. Mortgage assessment can allow for a card's full limit even when the balance is small. A transfer-cost comparison also does not decide eligibility or recommend refinancing.

Keep the repayment schedule with the assumptions used for the scenario. If you change the payment arrangement or keep spending on the card, calculate a new comparison before relying on the old total.