Debt Avalanche Calculator

The debt avalanche method is a debt repayment strategy where you focus extra payments on the debt with the highest interest rate first, while making minimum payments on all other debts. Once the highest-rate debt is paid off, you redirect those payments to the next highest-rate debt, and so on.

Why avalanche is mathematically optimal: By targeting the highest interest rate first, you minimize the total amount of interest paid over the life of all your debts. This makes it the most cost-efficient debt repayment strategy available.

How the calculation works:

1. List all debts with their balances, interest rates, and minimum payments
2. Allocate any extra monthly payment to the highest-rate debt
3. When that debt is paid off, add its minimum payment plus extra to the next highest-rate debt
4. Continue until all debts are cleared

The interest saved compared to making only minimum payments can be substantial. For example, a $10,000 credit card balance at 22% APR with a $200 minimum payment would take over 9 years to pay off and cost over $11,000 in interest. Adding just $100 extra per month cuts the payoff time to about 3 years and saves over $7,000 in interest.

Avalanche vs. Snowball method: The snowball method (targeting the smallest balance first) provides psychological wins by eliminating debts faster. The avalanche method saves more money overall. For most people, the interest savings of the avalanche method range from a few hundred to several thousand dollars compared to the snowball approach.

Key factors in the calculation:

• Total monthly budget — The more you can allocate above minimums, the faster you become debt-free
• Interest rates — Higher rate differentials between debts make the avalanche method more advantageous
• Balance sizes — Larger high-rate balances mean more savings from the avalanche approach

Important tips for success: Stop accumulating new debt while paying off existing balances. Build a small emergency fund first to avoid using credit cards for unexpected expenses. Consider balance transfer offers or debt consolidation if available at lower rates. Even small extra payments make a significant difference over time.

This simplified calculator models two debts for clarity. The same principle applies to any number of debts — always prioritize the highest interest rate for extra payments.