Juggling more than one debt makes a simple question surprisingly hard to answer by hand: which one should extra payments go toward first? A debt payoff calculator simulates the whole payoff month by month for either of the two standard strategies, so the answer comes from an actual calculation rather than a guess.
What "Free" Actually Means Here
- No account, no email, no login wall
- Results update live as you enter your debts
- Runs entirely in your browser — your balances and rates never get sent anywhere or stored on a server
- Works on desktop, tablet, or phone without an app
The Two Strategies
- Snowball — pay extra toward the smallest balance first, regardless of interest rate. Once it's paid off, roll that payment into the next-smallest balance.
- Avalanche — pay extra toward the highest interest rate first, regardless of balance size. Once it's paid off, roll that payment into the next-highest rate.
A Worked Example
Two cards: $1,200 at 8% APR, and $4,500 at 24% APR, with $150 extra available each month beyond the minimums.
- Snowball (small balance first): debt-free in 26 months, total interest $1,583.73
- Avalanche (high rate first): debt-free in 25 months, total interest $1,276.28
Avalanche wins on both counts here — one month faster and $307.46 less interest — because it tackles the 24% balance immediately instead of clearing the smaller, cheaper debt first.
Simulate your own debts with either strategy
Try the Debt Payoff Calculator