Snowball vs Avalanche Calculator

How it works

Both methods pay the same total each month, the sum of your minimums plus your extra, and both roll a cleared debt’s payment onto the next. The only difference is the order: the snowball goes smallest balance first for motivation, the avalanche goes highest rate first for the lowest cost. This calculator runs each in full and subtracts the interest totals:

With the defaults, three debts of $2,000 at 12%, $6,000 at 26%, and $9,000 at 8%, totalling $17,000, with $200 extra a month, the two methods split apart. The avalanche clears them in 44 months for about $3,941 in interest; the snowball takes 46 months and about $4,829, because it clears the small $2,000 debt first and leaves the 26% balance smouldering longer. Here the avalanche saves roughly $888.

The one time they tie is when your highest-rate debt is also your smallest, so both pay in the same order and the choice is only about momentum.

✓ Every result is checked against independent reference math. See how we test the calculators →

A worked example: three debts, $200 extra a month

Imagine three balances hitting at once: $2,000 at 12%, $6,000 at 26%, and $9,000 at 8%. You have $200 extra each month and want to know which payoff order costs less.

The snowball method, smallest balance first, clears everything in 46 months but runs up $4,829 in interest. The avalanche method, highest rate first, targets that 26% card and finishes in 44 months for $3,941. The gap is $888 kept in your pocket.

Both plans get you debt-free, so the difference is pure interest, not whether it works. Plug in your real balances and rates. When one debt carries a much higher rate, avalanche usually wins by more, and the calculator shows you exactly how much.

Picking your method

• Go avalanche if the gap is real. When this shows a meaningful saving, the highest-rate-first order is the cheaper route and worth the patience.
• Go snowball if you need momentum. When the difference is small, an early payoff win is often worth more than a few dollars of interest, because it keeps you in the game.
• Re-run as balances change. The recommendation can flip as debts clear or rates change, so check back every few months and adjust.

What drives the difference

The gap this calculator reports is not random; it is driven by the relationship between your balances and your rates. Two forces set it, and once you can see them you can usually predict which way a change will push the recommendation before you even re-run the numbers.

• How far apart your rates are. A wide spread, say a 26% card alongside an 8% loan, gives the avalanche a lot to save by killing the expensive debt first. Rates bunched close together leave little to gain.
• Whether your biggest debt is also your priciest. When a large balance carries the top rate, the avalanche’s edge is at its widest, because that is exactly the debt the snowball would leave for last.
• How much extra you pay. A bigger extra clears everything faster and compresses the gap between the two methods; a thin extra stretches the payoff and lets the difference grow.

Put together, the gap is widest when a large, high-rate debt would otherwise sit at the back of the snowball line, and narrowest when your smallest balance happens to be your most expensive. That second case is the tie the tool sometimes reports, where both methods pay in the same order and the choice comes down to momentum alone.

Reading the recommendation

Treat the recommendation as a starting point, not a verdict. The calculator names the cheaper method and the exact dollar gap, but the right choice also depends on something it cannot measure: which plan you will actually keep following until the last balance is gone.

• A large gap is a strong case for the avalanche. When real money is on the line, the highest-rate-first order is worth the patience it sometimes demands.
• A small gap tilts toward the snowball. If the avalanche saves only a little, the early wins of clearing whole debts may keep you on track better, and staying on track is what finishes the job.
• A tie is not a glitch. It means your smallest balance is also your highest-rate debt, so both methods pay in the same order. Pick either and put your energy into the plan, not the choice.

Re-run it as your situation changes, because the recommendation can flip. Paying off a debt, a promotional rate expiring, or adding a new balance all reshuffle the math. The honest question behind every result is the same: given these numbers, which method will you still be following a year from now?

Whichever the tool recommends, treat the first few months as a trial run. If you are keeping up and the plan feels sustainable, stay the course. If it feels punishing, switch methods rather than quit, because a slightly costlier plan you finish still beats the cheaper one you walk away from.

The comparison is meant to be a guide, not a cage.