Why several cards feel heavier than one
Each card has its own balance, its own APR, its own minimum and its own due date. Interest builds separately on every one of them. Paying the minimum on all of them can take a real chunk of the budget while every balance moves slowly.
The calculator puts every card on one timeline. Instead of tracking five separate countdowns, the results show a single plan with one finish month.
Entering each card
Each card needs its balance, APR and minimum payment, as they appear on the latest statement. The plan holds each minimum steady, even though many cards lower their minimum as the balance falls. Holding it steady is what lets the rollover work, because those dollars keep going toward the remaining cards instead of shrinking along with the balances.
If a minimum is lower than one month of interest on that card, the calculator raises it to interest plus $1 so the balance can still move, and flags the change.
One focus card, minimums on the rest
Every card gets its minimum payment each month. Any extra goes to one card at a time, called the focus card, and the order decides which card that is. Smallest balance first, highest rate first, or an order you set yourself are all options.
Which order costs less depends on the mix of balances and rates. The which debt to pay off first page ranks the orders, and the snowball vs avalanche calculator shows the gap between the two most common ones.
A card with a 0% intro rate stays at 0% in the calculator until its promo end month, then switches to its regular APR. That can change which card gets the focus, since a card that costs nothing today may cost the most later. The balance transfer calculator looks at that kind of promo on its own.
What happens when a card hits zero
When a card is paid off, its minimum does not leave the plan. It joins the extra and moves to the next card. Say three cards have minimums of $30, $45 and $60, and there is $100 of extra:
- The $100 extra goes to the first focus card, the one with the $30 minimum, on top of that minimum.
- Once the $30-minimum card is gone, the extra becomes $130.
- Once the $45-minimum card is gone, the extra becomes $175, going to the last card on top of its own $60 minimum.
The total going out each month stays the same; it just gets more concentrated as cards drop off. If the last payment on a card is only partial, the leftover moves to the next card that same month.
Reading the card-by-card results
The results list each card's payoff month and the order they clear, along with the overall debt-free month and total interest. Gaps between payoff months show where the rollover speeds things up: later cards often go faster because more money reaches them. All results are estimates that assume no new charges and steady rates.