Why This Calculator Exists
Most People Have More Than One Debt — And One Calculator Isn't Enough
The average American household carrying credit card debt has balances on more than two cards. Juggling three cards at 27%, 22%, and 18% APR with different balances and minimum payments is genuinely complex — and calculating the optimal payoff order by hand is impractical. That's what this tool solves.
By entering all your debts and your total monthly budget, you get a mathematically precise plan: exactly which debt to attack first, exactly when each one disappears, and exactly how much you'll pay in interest under both the avalanche and snowball approaches. The side-by-side comparison alone often reveals that one strategy saves $800–$2,000 over the other — that's a meaningful number worth knowing before you start.
How the Multi-Debt Algorithm Works
Every month, the calculator first allocates the required minimum payment to each debt. Any remaining budget is then applied to the target debt (highest rate in avalanche, smallest balance in snowball). When a debt is paid off, its minimum payment is freed up and automatically rolled into the next target — this is the "rollover" that makes both strategies increasingly powerful over time. The simulation runs month by month until every balance reaches zero.
💡 Which Strategy Should You Choose?
If your highest-rate debt also has one of the largest balances, the avalanche and snowball give similar timelines. The avalanche wins on total interest; the snowball wins on motivation. If you've started debt payoff plans before and quit, choose snowball. If you're motivated by data and can stay the course, choose avalanche. Either beats paying randomly.
The Power of the Debt Rollover
The most important mechanism in multi-debt payoff is the rollover. When Debt #1 is eliminated, the payment you were making on it doesn't disappear — it joins your attack on Debt #2. When Debt #2 is gone, both freed payments attack Debt #3. By the time you're fighting your last debt, you're making one large consolidated payment that wipes it out far faster than any of your original individual payments could. This exponential acceleration is why staying consistent — even when early progress feels slow — pays off dramatically at the end.