Keep required payments in view
Both approaches begin with the required payments on each debt. Additional money is then directed toward a selected balance. When that balance is cleared, the available payment is redirected to another debt.
Snowball: smallest balance first
The snowball approach prioritizes smaller balances. Clearing a small account sooner can make progress easier to see and reduce the number of outstanding accounts. However, a larger high-rate balance can continue generating interest while the smaller balance is paid.
Avalanche: highest rate first
The avalanche approach prioritizes the highest interest rate. Under a simple model with fixed rates, identical total payment budgets, and no special fees, directing extra principal to higher-rate debt generally reduces interest cost. Promotional rates, deferred-interest arrangements, and penalties can complicate the comparison.
A simple ordering example
Imagine $500 at 10% and $2,000 at 24%. Snowball targets the $500 balance first. Avalanche targets the 24% balance first. This example identifies the ordering only; it does not calculate a complete repayment schedule.
Know what this tool models
FinMathly’s Debt Payoff Calculator models one balance. It can show how extra monthly payments affect that debt, but it does not optimize a multi-account strategy. Keep a separate list of balances, rates, minimum payments, and special terms before comparing approaches.