List what you owe, add whatever extra you can put toward debt each month, and compare the two standard payoff strategies side by side.
Your debts
What you owe
Credit cards, car loans, personal loans, student loans: anything with a balance, an interest rate, and a minimum payment. Starting example numbers below; replace them with your own.
$
$0
Total minimums/mo
$0
Total monthly payment
Strategy comparison
Avalanche vs. snowball
Same debts, same total monthly payment either way, only the order changes. Debt avalanche always puts every extra dollar toward the highest interest rate first. Debt snowball always puts it toward the smallest balance first. A third option below skips the ordering question entirely: roll every debt into one new loan at a single rate, still paid with that same total monthly payment.
Debt consolidation
Roll everything into one new loan, same total monthly payment
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Balance over time
Which debts get paid off, and when, under each strategy
How the strategies work
Debt avalanche
Pay the minimum on everything, then put every spare dollar toward whichever debt has the highest interest rate. Once that one's paid off, its old minimum payment rolls into the next-highest-rate debt, and so on. This is the mathematically optimal order: no other order gets you debt-free faster or for less total interest, for the same total monthly payment.
Debt snowball
Same mechanics, different target: every spare dollar goes to whichever balance is smallest, regardless of its rate. You clear individual debts faster this way, which is the whole point: fewer open balances, sooner, tends to be easier to stick with than optimizing for interest alone. It usually costs a bit more in total interest than avalanche, sometimes takes a little longer overall, and is occasionally identical to avalanche (for example, with only one debt, or when the smallest balance also happens to carry the highest rate).
This calculator assumes interest compounds monthly on the current balance (balance × APR ÷ 12 each month) and that your total monthly debt payment stays constant until everything's paid off: a simplification of how real cards and loans compound, close enough for comparing strategies against each other. It doesn't account for promotional/introductory rates, balance transfer fees, or a rate that changes over time.