Debt Payoff Calculator
Determine how much you can save and how quickly you can become debt-free by making extra payments.
The Power of Extra Payments
A **Debt Payoff Calculator** demonstrates the significant financial advantage of paying more than the minimum required monthly installment. Because interest on most installment loans (like credit cards, personal loans, or mortgages) is calculated on the remaining principal balance, any extra money goes directly toward reducing that principal.
Key Calculation Concepts:
The calculator relies on solving the standard loan formula for time ($N$, the number of payments) and then calculating the total interest paid for both the original scenario and the new scenario with extra payments. The formula used to find the number of payments ($N$) is: $$ N = - \frac{\ln\left(1 - \frac{i \cdot P}{M}\right)}{\ln(1+i)} $$ Where:
- $P$ is the **Principal** Loan Balance.
- $i$ is the **Monthly Interest Rate** ($\frac{\text{APR}}{12}$).
- $M$ is the **Monthly Payment** (Current or New Total).
Savings and Time:
Even small extra payments can **drastically reduce the loan term** and **save thousands in interest**, as the principal decreases faster, reducing the amount of interest accrued in subsequent months.