Student Loan Calculator
Estimate monthly payments, total interest, and repayment costs for your student loan.
How This Student Loan Calculator Works
This calculator estimates your monthly student loan payments, total interest paid, and overall repayment cost. It applies the standard amortization formula used by most federal and private student loan servicers. The calculation assumes a fixed interest rate and consistent monthly payments over the full loan term.
What the Calculation Includes
- Loan Amount – The total principal you borrow or currently owe.
- Interest Rate – Your annual percentage rate (APR), which determines how much interest accrues each month.
- Loan Term – The repayment period in years, typically 10 years for standard federal loans but adjustable for private loans or extended plans.
- Monthly Payment – The fixed amount due each month based on the amortization schedule.
- Total Interest – The cumulative interest paid over the entire loan term.
- Total Cost – The sum of principal plus total interest.
Amortization Formula
The calculator uses the standard loan amortization formula:
M = P × [r(1+r)^n] / [(1+r)^n – 1]
Where M is the monthly payment, P is the principal, r is the monthly interest rate (annual rate divided by 12), and n is the total number of payments (term in years multiplied by 12).
How to Use the Student Loan Calculator
- Enter your loan amount – Input the total principal you plan to borrow or your current outstanding balance.
- Set your interest rate – Use the annual percentage rate from your loan agreement. For federal loans, this is fixed. For private loans, check your latest statement.
- Choose your loan term – Select the repayment period in years. Standard federal repayment is 10 years, but extended plans may go up to 25 or 30 years.
- Review your results – The calculator instantly shows your estimated monthly payment, total interest, and total repayment cost.
Example Calculation
Scenario: A borrower has a $35,000 federal student loan at a 5.5% fixed interest rate with a standard 10-year repayment term.
- Loan Amount: $35,000
- Interest Rate: 5.5%
- Loan Term: 10 years
- Monthly Payment: Approximately $380
- Total Interest Paid: Approximately $10,600
- Total Cost: Approximately $45,600
This means the borrower pays about $10,600 in interest over the life of the loan, making the total repayment $45,600.
Understanding Your Results
The monthly payment shown is the amount you would need to pay each month to fully repay the loan by the end of the term. This assumes no prepayments, deferments, or changes in interest rate.
The total interest figure represents the cost of borrowing. A higher interest rate or longer term increases total interest. A shorter term reduces total interest but increases the monthly payment.
These estimates do not include fees, late payment penalties, or changes in repayment plan. Actual payments may differ if you enroll in income-driven repayment, make extra payments, or refinance.
Common Mistakes When Estimating Student Loan Payments
- Using the wrong interest rate – Federal loans have fixed rates, but private loans may have variable rates that change over time. Always use your current rate.
- Ignoring loan fees – Some loans have origination fees deducted from the disbursed amount. This effectively increases the principal you need to repay.
- Assuming a standard term for all loans – Private loans may offer terms from 5 to 20 years. Federal loans have standard 10-year terms but offer extended and income-driven options.
- Forgetting about interest during school – Unsubsidized loans accrue interest while you are in school. This capitalized interest increases the principal when repayment begins.
Limitations of This Calculator
This calculator provides estimates based on a fixed-rate amortization schedule. It does not account for:
- Variable interest rates that may change over time
- Income-driven repayment plans where payments adjust annually
- Loan forgiveness programs such as Public Service Loan Forgiveness (PSLF)
- Deferment or forbearance periods
- Extra payments or prepayment penalties
- Capitalized interest from in-school or grace periods
For a complete repayment strategy, consult your loan servicer or a financial advisor.
Practical Use Cases
- Comparing loan offers – Evaluate different interest rates and terms from multiple lenders before borrowing.
- Planning monthly budget – Estimate how much of your monthly income will go toward student loan payments.
- Deciding between repayment plans – Compare standard, extended, and income-driven options to see which fits your financial situation.
- Evaluating refinancing – See how a lower interest rate or shorter term could reduce total interest costs.
- Assessing extra payment impact – Manually adjust the loan term to see how paying more each month shortens repayment and reduces interest.
Frequently Asked Questions
Does this calculator work for both federal and private student loans?
Yes. The amortization formula applies to any fixed-rate loan. For variable-rate private loans, the estimate is only accurate for the current interest rate.
What is the standard repayment term for federal student loans?
The standard repayment term for Direct Subsidized and Unsubsidized Loans is 10 years. Consolidation loans and PLUS loans may have terms up to 30 years depending on the balance.
Why is my actual monthly payment different from the calculator?
Actual payments may differ if you are on an income-driven repayment plan, have made previous deferments, or have capitalized interest that increased your principal. Always verify with your loan servicer.
Can I use this calculator for loans already in repayment?
Yes. Enter your current outstanding balance, interest rate, and remaining term to estimate your remaining payments and total interest.
Does the calculator include interest capitalization?
No. This calculator assumes interest is paid as it accrues. If you have capitalized interest from deferment or grace periods, your actual principal may be higher than the amount you originally borrowed.