Published 19 October 2026
A debt payoff calculator shows exactly when you'll be debt-free and how much interest you'll pay. For example, a €8,500 credit-card balance at 18% APR paid at €250 a month is cleared in about 48 months — costing roughly €3,478 in interest. Enter your balance below and try adding an extra monthly payment to see the difference.
Getting your payoff plan takes less than a minute:
The calculator updates live as you type, so you can experiment freely until you find a plan that fits your budget.
The calculator turns your APR into a monthly interest rate by dividing it by 12. An 18% APR, for instance, becomes a 1.5% monthly rate (0.18 ÷ 12 = 0.015). It then simulates your debt month by month: each payment covers that month's interest first, and the rest reduces the principal.
This simple order — interest first, principal second — is the reason minimum payments feel like a trap. Early on, a large share of your payment goes to interest, so the balance barely moves. As the balance shrinks, less interest accrues each month and more of every payment attacks the principal — which is why the last months of a payoff plan move fast while the first feel slow.
There is one critical condition: your monthly payment must be higher than the monthly interest. If it is not, the balance grows every month instead of shrinking — and the debt can never be cleared. The calculator checks for this and warns you, showing exactly how much interest your balance generates each month.
Take a €8,500 credit-card balance at 18% APR, paid at €250 per month. The monthly rate is 0.18 ÷ 12 = 0.015. The payoff month count follows the formula n = −ln(1 − 0.015 × 8500 ÷ 250) ÷ ln(1.015) ≈ 47.91, which rounds up to 48 payments: 47 full payments of €250 plus a final payment of €228.26.
The total paid is €11,978.26 and the total interest is €3,478.26 — over 40% of the original balance, charged simply for carrying the debt for four years.
Now add just €50 extra per month, for a €300 payment. The balance clears in about 38 months, with total interest of roughly €2,651 — 10 months sooner and about €827 less interest, from an extra €50 a month. Small, consistent extra payments compound into serious interest saved.
If you have more than one debt, the order you pay them in matters:
The avalanche — pay the minimum on every debt, then throw all extra money at the balance with the highest APR. When it is gone, roll that payment into the next highest rate. Mathematically this is the cheapest and fastest route: it minimizes total interest paid.
The snowball — pay minimums everywhere, then attack the smallest balance first regardless of rate. You clear individual debts sooner, which delivers motivational wins that keep many people on track longer.
Which is better? If you can stay disciplined without quick wins, the avalanche saves more money. If you have quit payoff plans before, the snowball's early victories may be worth the slightly higher interest cost. This calculator models one balance at a time — run each debt through it separately.
Enter your remaining balance, the APR on the debt, and your monthly payment. The calculator converts the APR to a monthly rate, then simulates your balance month by month — each payment covers that month's interest first, and whatever is left reduces the principal. It counts the months until the balance hits zero and turns that into a calendar date. Try adding an extra monthly payment to see how the date moves closer.
The avalanche method pays minimums on every debt and puts all extra money toward the highest-APR balance first. Mathematically it is the cheapest and fastest: it minimizes total interest. The snowball method attacks the smallest balance first regardless of rate, so you clear individual debts sooner and get motivational wins. If you can stay disciplined, choose the avalanche; if you need quick wins to stay motivated, choose the snowball. This calculator handles one balance at a time — model each debt separately.
As much as you can afford without risking missed bills elsewhere — even €50 a month makes a real difference. On a €8,500 balance at 18% APR paid at €250 a month, adding €50 (a €300 payment) cuts the payoff from about 48 months to about 38 months and saves roughly €827 in interest. The rule of thumb: automate the extra amount right after payday so it never sits in your account, and keep an emergency buffer of one month's expenses before you throw every euro at debt.
Your balance grows instead of shrinking. At 18% APR, the monthly rate is 1.5%, so a €10,000 balance generates about €150 of interest each month. If you pay only €150, the balance never moves; pay less and it increases every month — this is called negative amortization. The calculator flags this: if your payment does not cover the monthly interest, it shows the interest amount and tells you the debt will never be paid off. The fix is to raise the payment above the interest threshold, lower the APR, or both.
Yes — model each debt on its own, then use the avalanche strategy: pay only the minimums on every balance and direct all extra money at the debt with the highest APR until it is gone, then roll that freed-up payment into the next highest rate. Add up the individual results for your total interest and overall timeline. For a quick one-number estimate you can also combine balances, but the per-debt approach gives a truer payoff date.
The nominal monthly rate is the APR divided by 12. An 18% APR becomes a 1.5% monthly rate (0.18 ÷ 12 = 0.015). The calculator applies that rate to your remaining balance each month: interest = balance × 0.015. Your payment covers that interest first; the rest reduces the balance. Some lenders use daily compounding, which costs slightly more than the simple monthly division — so treat this as a close estimate and check your statement for the exact method.
Generally yes. Paying down revolving debt lowers your credit utilization — the share of your available credit you are using — which is one of the biggest factors in credit scoring. Dropping utilization below 30%, and ideally below 10%, typically lifts scores. A steady history of on-time payments also builds positive history. Your score may dip briefly when a very old account closes and shortens your credit history, but for most people the net effect of becoming debt-free is strongly positive.