Debt payoff order calculator
Enter up to three debts and compare paying them off smallest-first (snowball) vs highest-rate-first (avalanche).
Total debt over time
Combined balance across all your debts, month by month, under each method.
What this means for you
See how much extra you could put toward debt each month before it's paid off.
Compare extra payment amounts
Using the avalanche method throughout, see how a bigger extra payment speeds things up.
| Scenario | Extra / month | Debt-free in | Total interest |
|---|---|---|---|
| Current | $0 | 0 | $0 |
| +$100/month | $0 | 0 | $0 |
| +$200/month | $0 | 0 | $0 |
All three rows use the avalanche method, since it's mathematically the cheapest — this isolates the effect of the extra payment amount alone.
Assumptions & sources
The interest rates and minimum payments you enter for each debt.
1 July 2026
17 July 2026
Month-by-month simulation: each debt accrues interest, minimum payments are applied, then the extra — plus the freed-up minimums of any cleared debts — is directed to the target debt (highest rate for avalanche, smallest balance for snowball) until all debts reach zero.
Up to three debts, their interest rates, minimum payments, and any extra you can put toward debt each month.
Any fees, rate changes over time, or new debt taken on during the payoff period.
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Read article →Snowball vs avalanche, in plain terms
Both methods pay the minimum on every debt, then throw every spare dollar at one target debt until it's gone, then roll that payment into the next target. The only difference is which debt you target first. Avalanche targets the highest interest rate, which mathematically minimises total interest paid — it's the objectively cheaper method every time balances and rates differ.
Snowball targets the smallest balance instead, which usually means winning your first "debt-free" moment faster, even if it costs a bit more overall. For many people that early win is worth more in motivation than the extra interest costs in dollars — this calculator shows you exactly how much that motivation costs, so you can decide if it's worth it for you.
Example: A $3,000 car loan at 11% vs an $8,000 credit card at 21%
Sina has a $3,000 car loan at 11% p.a. and an $8,000 credit card balance at 21% p.a., plus $200 a month extra to put toward whichever she tackles first.
Avalanche has her attack the credit card first, since 21% is the higher rate — even though it's the bigger balance. This minimises the total interest she pays across both debts.
Snowball has her attack the smaller $3,000 car loan first instead. She'd hit her first "debt-free" milestone several months sooner, which can be worth a lot for staying motivated — but the $8,000 balance keeps accruing at 21% for longer, so she pays more in total interest overall.
Neither answer is wrong — it depends on whether Sina needs the early win to stay motivated or can stick with the plan either way. Try both scenarios above with your own numbers to see the actual dollar gap for your situation.
Frequently asked questions
Snowball pays off the smallest balance first regardless of rate, building momentum through quick wins. Avalanche pays off the highest interest rate first, which minimises total interest — snowball can cost more overall but its early wins keep some people more consistent.
Avalanche always saves the same or more interest, so it's mathematically better. Snowball can still be the better real-world choice if clearing a debt fully keeps you motivated — the best method is the one you'll actually stick to.
