Debt Avalanche Calculator
The debt avalanche pays the highest APR first while every other debt gets its minimum. Each extra dollar goes where it cancels the most interest, so the avalanche is the order that costs the least in total. Enter your debts below to see the order, the interest you pay under it, your debt-free date, and how much it saves against the snowball and against paying only minimums.
How the avalanche order is built
Debts are sorted by APR, highest first. All of the extra money goes to the first debt in that order, and when it clears, its minimum and the extra roll onto the next highest rate. Two debts at the same APR are ordered by balance, smaller first, so you still see a payoff sooner. The order is recomputed every month, which matters only when rates tie.
Interest is charged once a month at APR ÷ 12 on the current balance, then payments land. The monthly total stays fixed for the whole plan.
Why the avalanche minimises interest
Interest on each debt is its balance times its rate. Moving a dollar from a 7% loan to a 29% card saves 22 cents a year, every year, for as long as that dollar would have sat on the card. The avalanche applies that logic every month, so no other order with the same monthly payment pays less interest. The panels above show the saving against the snowball in dollars; on lists where the rates are close it can be small.
Avalanche vs minimums only
The dashed line on the chart is what happens if you pay only the minimums. The gap between it and the avalanche line is the whole argument for an extra payment: months cut from the plan and interest never charged. Both figures are shown under the avalanche panel.
Frequently asked questions
What is the debt avalanche method?
A payoff order: pay the minimum on every debt and put everything else toward the debt with the highest APR. When it is paid off, roll its payment onto the next highest rate, and continue until the last debt clears.
Is the debt avalanche the cheapest way to pay off debt?
For a fixed monthly payment across the same debts, yes: it pays the least total interest of any payoff order, because each extra dollar removes the most expensive balance first. It does not always finish sooner than the snowball, but it never costs more.
What if two debts have the same APR?
The calculator pays the smaller balance first among equal rates, so you still get a payoff sooner at no extra interest cost. That is the same tie-break the Debt Ladder app uses.
Does a 0% promotional balance belong in the avalanche?
Yes, at the bottom of the order — a 0% debt costs nothing to carry. If the promotional rate ends on a date, enter the rate it will revert to if you want to be conservative.
Is this financial advice?
No. The calculator applies one rule to the numbers you type and shows the result. It does not evaluate your circumstances or recommend products. Speak with a qualified professional for advice.
Keep the plan going in Debt Ladder
Debt Ladder is the app behind this calculator. It uses the same payoff engine, then keeps the plan alive: a monthly check-in to log what you actually paid, extra payments on any day for any amount, and a debt-free date that moves as you go. Private and on your phone — no account, no bank linking, no ads. Scan the QR code above to carry this plan into the app.