How does a credit card payoff calculator work?

A credit card payoff calculator estimates monthly interest from each card's APR, applies minimum payments, applies any extra payment to the selected payoff method, and repeats the process until all balances are paid or the model reaches its time limit.

Is avalanche or snowball better for paying off credit cards?

Avalanche usually saves the most interest because extra money goes to the highest APR card first. Snowball pays the smallest balance first, which can close an account sooner and may help with motivation.

Why can minimum payments take so long?

Credit card minimums can be close to the monthly interest charge. When most of the payment goes to interest instead of principal, the balance may fall slowly or fail to amortize in a reasonable time.

Does this calculator store my debt numbers?

No. The calculator runs in your browser. It has no analytics, no account system, and no form that submits your debt data anywhere.

Credit Card Payoff Calculator

Your Cards

Add balances, APRs, and current minimum payments. The calculator fills a useful sample to start.

Card Name	Balance ($)	APR (%)	Minimum ($)	Promo

Up to 20 cards.

Installment Loans (optional)

Add fixed-payment debts such as personal, auto, or student loans.

Loan Name	Balance ($)	Interest Rate (%)	Fixed Monthly Payment ($)	Remaining Term (months)

Payoff Method

Extra Monthly Payment ($)

Applied after all active debts receive their required minimum or fixed payment.

Start Month

Target Payoff Date

Optional. Shows the monthly payment needed by that month.

Balance Over Time

Stacked area shows each debt's remaining balance; the dark line shows total balance.

Payoff Method Comparison

Compare avalanche, snowball, and minimum-only using the same card inputs.

Method	Payoff Date	Months	Total Interest	Monthly Payment	First Card Paid

Month-by-Month Schedule

First 24 months shown by default.

Month	Date	Payment	Interest	Principal	Ending Balance	Extra Target

Methodology

Each month, the calculator computes interest for every active card using APR divided by 12. It then uses the greater of the issuer-style minimum estimate, the entered minimum payment, or $25, capped at the amount needed to pay the card off that month.

The issuer-style minimum estimate is current balance times 1% plus that month's interest. The payment first covers interest, then reduces principal. Avalanche applies extra money to the highest APR card until it is paid, then cascades. Snowball applies extra money to the smallest balance until it is paid, then cascades. Minimum only applies no extra payment.

The schedule stops when all balances reach $0 or after 600 months. Results are estimates and do not include new charges, fees, promotional APRs, penalty APRs, payment timing differences, or issuer-specific minimum rules beyond the model above.

FAQ

What payment do I need to be debt-free by a target date?

Enter a target payoff month. The calculator uses a binary search over monthly payment amounts and reports the smallest estimated payment that pays all entered cards by that month.

What is the debt avalanche method?

Avalanche pays every card's minimum, then sends extra money to the highest APR card. It is usually the lowest-interest method.

What is the debt snowball method?

Snowball pays every card's minimum, then sends extra money to the smallest balance. It may cost more interest, but it can produce a faster first payoff.

Why does minimum-only sometimes show a warning?

If a card's minimum payment is less than or equal to the monthly interest charge, principal does not shrink. The calculator flags that as a revolving trap.

Can I use this offline?

Yes. This is a single self-contained HTML file with client-side calculations. After the page is loaded or saved, it can run without a network connection.