Student Loan Repayment Calculator
Calculate student loan payoff time, total interest paid, and total cost.
Enter your loan amount, interest rate, and monthly payment.
Repayment Summary
Student Loan Repayment is calculated using the amortization formula. Each monthly payment covers interest first, then reduces the principal.
Monthly interest:
Monthly Interest = Remaining Balance × (Annual Rate / 12)
Time to pay off depends on your monthly payment amount. Higher payments mean faster payoff and less total interest.
Key formulas:
Monthly Interest Rate = Annual Rate / 12Months to Pay Off = -ln(1 - (Balance × Monthly Rate / Payment)) / ln(1 + Monthly Rate)Total Paid = Monthly Payment × Number of MonthsTotal Interest = Total Paid - Original Loan Amount
Important: Your monthly payment must exceed the monthly interest charge, or the loan will never be paid off.
Federal student loan rates (2025-2026):
- Direct Subsidized/Unsubsidized (undergraduate): 6.53%
- Direct Unsubsidized (graduate): 8.08%
- Direct PLUS: 9.08%
Tips to pay off faster:
- Pay more than the minimum each month
- Make bi-weekly payments (26 half-payments = 13 full payments/year)
- Apply windfalls (tax refunds, bonuses) to principal