Use this Student Loan Calculator to estimate your required monthly payment, total interest, payoff date, and potential savings from paying extra toward a fixed-rate student loan.
Enter the balance expected when repayment begins, the fixed annual rate, the repayment term, and an optional extra monthly payment.
Monthly payment, payoff, and amortization estimates will appear here.
| Year | Starting Balance | Payments | Principal Paid | Interest Paid | Ending Balance |
|---|
A Student Loan Calculator estimates the payment and repayment cost of a student loan using the balance, fixed interest rate, and repayment term. This version also compares the standard schedule with an optional extra monthly payment.
Use the result to understand how the loan term and interest rate affect monthly cost, total interest, and payoff time. The calculation is an estimate, not a loan offer or a replacement for your lender's billing information.
M = P × [r(1 + r)ⁿ] ÷ [(1 + r)ⁿ − 1]
In the formula, P is principal, r is the monthly interest rate, and n is the total number of monthly payments. At a 0% rate, the balance is divided equally across the selected number of months.
Review how StudentCalcTools documents formulas, assumptions, input handling, simulation limits, rounding, testing, and privacy.
Use the principal expected when repayment begins, including any capitalized interest already added to the loan.
Enter the fixed annual interest rate shown in your loan records or servicer account.
Select the number of years over which the balance will be repaid under the fixed-payment estimate.
Add an amount above the required payment to estimate potential interest and time savings.
Principal is the unpaid loan balance. Interest is the cost charged for borrowing. In a fixed-payment amortization schedule, every payment covers interest and principal, but the split changes as the balance falls.
More of the payment usually goes to interest because interest is calculated on a larger unpaid balance.
As principal falls, less interest accrues and more of each scheduled payment reduces the remaining balance.
Federal Direct Loans generally accrue interest daily, so the exact amount can vary with payment timing and the number of days between payments.
Unpaid interest may sometimes be added to principal. When that happens, future interest can be calculated on a higher balance.
Paying more than the required amount can reduce the balance faster and lower future interest. The calculator applies the extra amount every month after the required payment and estimates a new payoff schedule.
Payments are generally applied to outstanding fees and interest before principal. Servicer instructions matter when you want additional money directed toward principal or a specific loan.
This calculator estimates a conventional fixed monthly payment. Federal income-driven repayment plans use additional information and may produce a payment that differs substantially from a standard amortization result.
| Estimate Type | Primary Inputs | What It Shows | Best Tool |
|---|---|---|---|
| Fixed-payment estimate | Balance, fixed rate, and term | Level monthly payment, total interest, and payoff schedule | This Student Loan Calculator |
| Federal repayment-plan estimate | Loan type, income, family size, tax information, and plan rules | Possible payments under available federal plans | Federal Student Aid Loan Simulator |
| Variable-rate private loan estimate | Balance, current rate, future rate changes, and contract terms | Scenario-dependent payment and cost | Your lender's calculator or disclosures |
The same fixed-rate amortization formula can estimate many federal and private loans, but the surrounding terms may differ. Federal loans may offer repayment plans and protections that are not available on private loans. Private loans may have fixed or variable rates and lender-specific repayment terms.
For multiple loans, calculate each balance separately when rates differ. A single combined estimate can hide the effect of high-rate loans and may not match how a servicer applies payments.
The calculator uses a standard fixed-payment amortization model. The surrounding guidance is based on official federal student aid and consumer-finance resources covering interest rates, repayment-plan comparison, payment application, and additional payments.
Compare monthly affordability with total interest and payoff time. A lower monthly payment can make the budget easier while increasing the total amount repaid over a longer term.
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