Debt Snowball Calculator

Each month: pay every minimum, then send all extra to the smallest remaining balance. When it clears, its whole payment rolls onto the next-smallest — the snowball grows.

How the snowball builds momentum

The debt snowball ignores interest rates and goes after the smallest balance first. You pay the minimum on every debt, then throw every spare unit of money at the smallest one until it is gone. The moment it clears, its entire payment — minimum plus the extra you were adding — rolls onto the next-smallest debt. That debt now falls even faster, and when it clears its payment rolls on again. The payment you put toward debt grows like a snowball rolling downhill, and the calculator shows each balance vanishing one by one.

The point is psychological, not mathematical. Clearing a whole debt early — seeing an account hit zero — is a powerful motivator that keeps people going. The snowball trades a little extra interest for momentum, and for many people that trade is what makes the difference between finishing and giving up.

Worked example — three debts ($1,500 at 15%, $6,000 at 19%, $11,000 at 8%) with $300 extra a month: The $1,500 debt clears first — often within a few months — and its payment rolls onto the $6,000. The calculator shows your debt-free date, each clear date, and exactly how much extra interest the snowball costs versus the avalanche.

The honest trade-off vs the avalanche

The avalanche method targets the highest interest rate first and always pays the least total interest — it is the mathematically optimal choice. The snowball usually costs a little more, because it may leave a high-rate debt sitting longer while you clear a smaller, cheaper one. This calculator shows both, side by side, and the exact extra interest the snowball costs you. That is the honest trade-off: a number you can look at and decide whether the motivation is worth it.

For many people the gap is surprisingly small — a few months and a modest sum — and the behavioural edge of quick wins more than makes up for it. If the gap is large in your case, you will see it here and can choose with open eyes. The best plan is the one you actually finish.

Speeding the snowball up

Anything extra accelerates the snowball. A one-time windfall — a bonus, tax refund or gift — applied to the current target debt clears it sooner and brings the next win forward. And stepping your payment up over time, as your income grows, compounds throughout the plan. Both are in the advanced options.

A note on scope: this tool assumes the fixed minimum payments you enter. Real credit cards often set the minimum as a percentage of the balance, which falls as the balance does — so on the debts you are not yet targeting, a real minimum may drift slightly from the figure here. For the debt you are actively snowballing, where you pay far more than the minimum, the result is accurate.