How to Use the Student Loan Calculator
- Add up your loan balances, or run each loan separately.
- Enter the interest rate and choose a repayment term.
- Optionally enter an extra amount you could pay each month.
- Press Calculate.
- Compare the standard path with the extra-payment path in the chart.
Formula
Payment = B × r ÷ (1 − (1 + r)^−n) Each month: interest = balance × r; principal = payment + extra − interest Repeat until the balance reaches zero.
Example Calculation
A $35,000 balance at 5.5% over 10 years has a payment of about $380 and total interest near $10,600. Adding $100 a month would pay the loans off roughly two and a half years sooner and save nearly $2,900 in interest.
What Is a Student Loan Calculator?
It estimates the monthly payment and total interest for a fixed-rate student loan and shows how changing the term or adding extra payments alters the outcome.
How Student Loan Interest Works
Interest accrues on the outstanding principal. Early in repayment, most of each payment covers interest; later, more goes to principal. Extra payments early on have an outsized effect because they reduce the balance that generates future interest.
Federal vs Private Loans
Federal loans offer protections such as income-driven plans and certain forgiveness programs. Private loans typically do not. Before refinancing federal loans into a private loan, consider what you would be giving up.
Tips
- Run each loan separately if the rates differ and target the highest rate first.
- Automate payments to avoid missed due dates.
- Keep an emergency fund so a surprise expense does not derail repayment.
Common Mistakes
- Choosing the longest term by default.
- Ignoring capitalized interest after deferment.
- Paying extra without telling the servicer where to apply it.
Managing several debts at once? The debt payoff calculator compares avalanche and snowball strategies.