Last updated October 5, 2026 · Report an error
A student loan's balance, interest rate, and repayment term together determine a fixed monthly payment — and how much of that payment goes toward interest versus principal over the life of the loan.
This calculator finds the standard monthly payment and total interest for a student loan using the same amortization formula banks use.
How it works
Enter your total student loan balance, the annual interest rate, and the repayment term in years. The calculator applies the standard loan amortization formula to find the fixed monthly payment, then multiplies it out to find the total amount paid and total interest over the full term.
- Enter total student loan balance ($).
- Enter annual interest rate (%).
- Enter repayment term (years).
- Click Calculate to see your results.
Examples
A $30,000 loan over 10 years
A $30,000 balance at 5.5% over 10 years costs about $325.58 per month — roughly $9,069.60 in total interest.
Who should use it
- Estimating monthly payments before taking out a student loan.
- Comparing the cost of different repayment terms on an existing loan.
Industry applications
- Personal finance and student loan planning
- Financial aid counseling
Advantages
- Uses the same standard amortization formula lenders use.
- Shows total paid and total interest, not just the monthly payment.
Limitations
- Doesn't model income-driven repayment, deferment, forbearance, or loan forgiveness programs.
Common mistakes to avoid
- Comparing loan offers by monthly payment alone without checking the total interest paid over the full term.
- Forgetting that federal and private student loans often have very different rate structures and repayment options.
Best practices
- Compare the total interest paid, not just the monthly payment, when choosing between different loan terms.
Tips
- Making extra payments toward principal, even small ones, can meaningfully reduce total interest paid over the life of a student loan.