Calculator
Debt payoff calculator: avalanche vs snowball
Enter your debts once. See how much sooner you clear them and how much interest you save, under the highest-rate-first method and the smallest-balance-first method.
Avalanche is always cheaper — mathematically, paying the highest rate first minimises total interest, with no exceptions. Snowball clears individual debts sooner, which some people find motivating enough to stick with. Look at the gap above: if avalanche only saves a few hundred dollars, pick whichever you will actually follow. If it saves thousands, the maths deserves the vote.
How this is calculated
- Interest accrues monthly on each balance at
APR / 12. - Every debt receives its minimum each month. The extra payment goes entirely to one target debt: the highest APR (avalanche) or the smallest balance (snowball).
- When a debt clears, its minimum rolls into the extra payment — this is what makes both methods accelerate.
- Minimums are treated as fixed. Real credit cards usually recalculate the minimum as a percentage of the balance, which makes minimum-only payoff slower and more expensive than shown.
- Fees, promotional rates, penalty APRs and balance transfers are not modelled.
Before you optimise the order
Two things matter more than avalanche versus snowball. Stop adding to the balance — no payoff strategy survives continued borrowing on the same cards. And check whether a lower rate is available: a balance transfer or consolidation loan at a materially lower APR beats any reordering of payments at the old rate. Read the transfer fee and the rate after the promotional period before you move anything.
One exception to paying debt first: if your employer matches retirement contributions and you are not capturing the full match, take the match. An instant 50% return beats paying down even a high-rate card.
Common questions
What is the difference between the avalanche and snowball methods?
Both pay the minimum on every debt and put all spare money into one target debt. Avalanche targets the highest interest rate, which minimises total interest paid. Snowball targets the smallest balance, which clears individual debts faster and gives quicker visible wins.
Which method saves more money?
Avalanche, always, because interest is what costs you and the highest rate accrues fastest. The size of the advantage varies enormously with your particular mix of debts, though. This calculator shows the gap for yours, which is the number that should decide it.
Should I pay off debt or invest?
Compare the interest rate to the return you could reasonably expect. Paying off a 22% credit card is a guaranteed 22% return and beats essentially any investment. A 4% subsidised student loan is a much closer call. The one thing that comes before both is capturing a full employer retirement match.
Why does minimum-only payoff take so long?
Because the minimum on a high-rate card is set close to the interest accruing on it, so very little of each payment touches the principal. Note that real cards usually shrink the minimum as the balance falls, which stretches it out even further than this calculator shows.
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