Debt Payoff Calculator: Snowball vs Avalanche
Line up every debt, add whatever extra you can pay each month, and watch two proven payoff orders race: snowball (smallest balance first) versus avalanche (highest interest rate first).
How to use this calculator
Run the numbers once, write the result where you will see it, and let the free expense tracker do the weekly work: it sorts every entry into needs, wants and savings automatically, so drift from the plan is visible the moment it starts instead of at the end of the month. A calculator sets the target; tracking is what actually gets you there.
The two methods in one sentence each
Avalanche always throws every spare dollar at the debt with the highest interest rate — mathematically optimal, minimum total interest. Snowball throws spare dollars at the smallest balance first, ignoring rates — psychologically optimized, because clearing a whole account in week six is the proof of progress that keeps people paying. The calculator runs both to the finish line on your real numbers, so the debate stops being philosophy and becomes two dollar figures: months to debt-free, and interest paid.
How the simulation runs, month by month
Each month every balance grows by its monthly interest, every account gets its minimum payment, and then whatever is left — your extra amount plus the minimums of anything already cleared — lands on the current target. That roll-over mechanic is the real engine: clear the $800 card and its $25 minimum joins the attack fund, so progress accelerates every time an account dies. It is also why the extra payment row matters more than the order: an extra $100 usually changes the timeline by years, while the method choice changes it by months.
Extra payments beat refinancing for small balances
Balance-transfer offers and consolidation loans get all the attention, but they carry fees, teaser rates that expire, and a fresh credit line people inevitably reuse. Extra principal has none of those failure modes: it shortens the timeline permanently, saves interest at the original rate, and every retired account is one bill and one temptation gone. Run the simulation with the extra amount at zero, then at your realistic number — the difference is the honest price of the subscription you could cancel to fund it.
The order that works is the one you finish
If the two methods come out within a few months and a few hundred dollars of each other on your numbers, pick the one whose first win you can picture — the quick kill is worth more than the optimal interest curve you abandon in month four. If avalanche comes out dramatically cheaper and you have the discipline of a spreadsheet, run it. The calculator showing a small gap is permission to choose motivation over math without guilt.
Frequently asked questions
Which method saves more interest?
Avalanche, always — by construction it targets the most expensive money first. The interesting number is by how little: on many real debt lists the gap is a few hundred dollars, which is why snowball stays popular.
What if I cannot cover the minimums?
Then this calculator is the wrong tool — contact each lender about hardship plans first, and a nonprofit credit counseling agency before any debt-settlement company. The simulation assumes the minimums are payable.
Should I empty savings to pay debt?
Keep one month of essential expenses in cash first, or the next flat tire goes straight back on the card. Above that buffer, money earning 0.5% while your card charges 22% is a losing trade.