Credit Card Payoff Calculator

How credit card payoff math works

Credit card interest compounds monthly, and the calculation is short enough to do by hand. Take the balance, multiply it by the annual percentage rate divided by 12, add that interest to the balance, then subtract whatever you paid. What is left is next month's starting balance. Repeat until the balance hits zero.

Two things follow from that loop, and they explain almost everything people find surprising about credit card debt. First, the interest charge is calculated on the balance at the time, so a large balance early in the payoff generates the biggest charges, the first month on a $5,000 balance at 22% costs about $91.67 in interest alone. Second, every extra dollar you pay goes entirely to principal, which means it also removes all the future interest that dollar would have generated. That is why small increases in payment have outsized effects.

The calculator above runs the loop month by month and reports three numbers: how many months until the balance is zero, the total interest you will pay, and the total you will hand over. It also shows what happens if you pay more, which is usually the most useful output on the page. For the official rules on how interest must be disclosed and applied, the Consumer Financial Protection Bureau's credit card tools are the authoritative starting point.

Worked example: $5,000 at 22% APR paying $250

This is the most common shape of credit card debt in the US: a balance around $5,000 and an APR in the low twenties. Paying a fixed $250 a month:

• Months to pay off: 26
• Total interest paid: $1,285.72
• Total paid: $6,285.72
• Interest as a share of the original balance: 25.7%

Look at the first few months to see where the money goes. Month 1: interest of $91.67 on $5,000, so $158.33 of your $250 goes to principal. Month 12: the balance is down to about $2,900, interest is $56.64, and $193.36 goes to principal. Month 25: interest is down to $5.13 and almost the whole payment attacks the balance. By the end, the final payment is about $36 instead of $250, and the last year of the payoff feels nothing like the first.

Now change one variable. Keep the balance and the rate, and pay $150 instead of $250. The payoff stretches to 52 months, four years and four months, and the interest more than doubles to $2,798.05. Paying $100 less every month costs $1,512.33 more in interest and adds more than two years. The reverse is just as dramatic: $350 a month clears it in 17 months with $851.20 of interest, saving $434.52 and 9 months for an extra $1,700 paid.

What an extra $50 a month buys you

People are told to pay more, but rarely shown the number. Here it is for a $5,000 balance at 22% APR.

The first $50 you add, from $150 to $200, saves more than any later $50, because it attacks the balance while the balance is still large and generating the most interest. Going from $150 to $200 saves $1,048.17 and removes 18 months. Going from $300 to $350 saves only $170.40 and removes 4 months. Diminishing returns set in quickly, but the early dollars are extremely efficient.

A useful way to think about it: at $150 a month, the interest is 56% of the original balance. At $250 it is 26%. At $500 it is 11%. Every increase in payment cuts the interest share roughly in proportion, which means the difference between a comfortable minimum and an aggressive payoff is the difference between paying for the card twice and paying for it once.

Why minimum payments can trap you for decades

A minimum payment is not designed to clear a balance. It is usually a percentage of the balance, 1% to 3%, with a dollar floor, which means the payment shrinks as the balance falls, and the shrinking payment keeps the payoff in the distant future.

Seven hundred and sixty-seven months is nearly 64 years. The mechanism is simple: the payment tracks the balance down, so it reaches the $35 floor while the balance is still large, and from that point the interest on the remaining balance is close to the entire payment. In the worst case the payment does not even cover the interest, and the balance grows every month.

That is not hypothetical. At 29.99% APR, a $5,000 balance accrues about $124.96 of interest in the first month. A 2% minimum payment on $5,000 is $100, less than the interest. Pay the minimum and the balance goes up, not down, and no amount of patience will fix it. The only way out is a payment that is fixed and comfortably above the monthly interest, which is exactly what this calculator is built to show you. If you are already in that situation, the CFPB's consumer question library and a nonprofit credit counselor are better resources than any calculator.

Balance transfers, new charges and the traps around them

Moving a balance to a lower rate is the single fastest lever available, and it comes with three caveats. The transfer fee. A typical fee is 3% to 5% of the amount moved, charged upfront. Moving $5,000 at 3% costs $150 before you have saved a cent. On a 22% balance that fee is roughly equivalent to two months of interest, so a transfer only wins if you carry the balance for more than about two months.

The promotional window. A 0% intro rate usually runs 12 to 21 months. If you clear the balance inside the window you win outright. If you do not, the remaining balance reverts to the card's standard rate, which is often higher than the rate you transferred from, so a partial payoff can leave you worse off than doing nothing.

New charges. This is the trap that catches the most people. Keep using a transferred card and new purchases typically carry the standard rate immediately, while payments are applied to the cheapest balance first. The result is that the 0% balance sits there untouched while the new charges accrue interest at 25%. If you transfer a balance, stop using that card.

Two other habits quietly undo progress. Cash advances usually start accruing interest the same day with no grace period and often at a higher rate. And a missed payment can void a promotional rate outright, resetting the whole balance to the standard APR and sometimes triggering a penalty rate on other accounts as well. Set the autopay for at least the minimum on every card you hold, even the ones you are not focusing on.

What this estimate leaves out

The calculation here is deliberately simple, and four things can make the real answer different. The APR is not always the rate you pay. Variable-rate cards are tied to an index, and the rate moves when the index moves. A card quoted at 22% today may be 24% next year without any change in your behaviour. The Federal Reserve's consumer credit data shows how average card rates have moved over time.

Interest is usually computed on an average daily balance, not a month-end balance. For a card you are actively paying down, that means slightly less interest than this calculator shows. The direction is in your favour, and the size of the difference is small, usually under a few dollars a month on a $5,000 balance.

Fees and new spending. Late fees, annual fees and any new purchases are not modelled. New spending is the big one: if you pay $250 a month but charge $200 of new purchases, the payoff time roughly doubles. A payoff plan only works if the card stops being used.

Taxes. Credit card interest on personal debt is not deductible, so every dollar of interest is paid out of income that has already been taxed. There is no tax benefit to carrying a balance, and nothing in this calculator takes your tax situation into account. If the balance is business-related, that is a different question and one for a tax professional.

This is an estimate, not financial, legal or tax advice. It assumes a fixed APR and no new charges. For guidance about your own situation, a nonprofit credit counselor or your lender is the right place to go.