Free Debt Payoff Calculator: Snowball vs. Avalanche Plan

Our interactive calculator compares the two most reliable debt payoff frameworks—the Debt Snowball (behavioral momentum) and the Debt Avalanche (mathematical efficiency). Enter your debts below to generate your personalized amortization schedule, monthly payment breakdown, and exact debt-free month.

Privacy Assurance: All balance entries and calculations are processed directly inside your browser sandbox. No account registration is required, and no financial data is transmitted to external servers.

1. Instructions for Use

  1. List all non-mortgage debts: Enter credit cards, personal loans, medical bills, auto notes, and student loans.
  2. Input three data points per debt: Current balance, Annual Percentage Rate (APR), and required monthly minimum payment.
  3. Enter your extra monthly budget: Add any surplus cash you can dedicate above total required minimums (e.g., $50, $150, or $300).
  4. Toggle payoff strategy: Instantly compare Debt Snowball vs. Debt Avalanche to see differences in total interest and payoff speed.

2. Example Scenario

A common 3-debt household scenario illustrates the calculation:

  • Debt 1 (Store Card): $800 balance at 26.99% APR (Min: $28/mo)
  • Debt 2 (Major Visa): $3,200 balance at 21.49% APR (Min: $90/mo)
  • Debt 3 (Car Loan): $6,500 balance at 7.50% APR (Min: $185/mo)
  • Extra Monthly Payment: $150/mo added to priority target debt

3. Underlying Assumptions

  • Standard Monthly Compounding: Periodic monthly rate equals APR / 12, reflecting standard monthly billing statements.
  • No Additional Charges: Assumes credit cards are frozen and no new retail charges, balance transfer fees, or late penalties accrue during repayment.
  • Rollover Discipline: As each debt is extinguished, 100% of its former minimum and extra payment rolls into the next prioritized target account.

4. Limitations & Scope

  • Variable APR Fluctuations: Variable-rate credit cards may adjust over time with Federal Reserve interest rate decisions.
  • Average Daily Balance: Actual card issuer interest may vary by several dollars due to 28-to-31 day statement cycle day counts.
  • Educational Simulator: My Debt Off is an educational planning model, not a licensed debt settlement or lending service. Read our Mathematical Methodology for complete equations.