Student Loan Calculator

See your monthly student loan payment, what it costs over the life of the loan, and how much faster extra payments get you debt-free.

By the CalculateBright team · Updated · How we calculate

Example: federal undergraduate Direct Loans were 6.39% for 2025–26
Repayment term
  

    How to use the Student Loan calculator

    1. Enter your numbers. Fill in loan balance, interest rate, repayment term, extra monthly payment.
    2. Read your results. Results update instantly. The headline shows the monthly payment; the breakdown and table below show the details.

    How student loan payments are calculated

    Federal and private student loans in repayment are fixed-payment installment loans. The calculator applies the standard amortization formula to your balance, rate and term. The federal Standard Repayment Plan is 10 years; extended and consolidation plans run up to 25 or 30 years.

    Payment = Balance × r ÷ [1 − (1 + r)−n]

    where r is the monthly rate (APR ÷ 12) and n the number of monthly payments.

    Term vs. total cost

    On a $35,000 balance at 6.39%, a 10-year plan costs about $395 a month and $12,400 in interest. Stretching to 25 years drops the payment to about $234 but more than doubles the interest. The comparison table shows this trade-off for your numbers.

    What this calculator doesn’t model

    Income-driven repayment, Public Service Loan Forgiveness and the federal repayment changes in the 2025 budget law depend on your income, family size and loan type. Use the official Federal Student Aid Loan Simulator for those. Private refinancing offers can be compared here directly by entering the new rate and term.

    Worked example

    With these inputs: loan balance $35,000; interest rate 6.39%; repayment term 10y.

    The calculator gives a monthly payment of $395.46 (10-year plan). Other results: total interest $12,455, time to pay off 10 yr, payoff date Oct 2036, 10-year standard plan payment $395.46/mo.

    What your results mean

    The monthly payment is what keeps you on schedule for the term you picked. Total interest is the extra you pay to borrow. The term comparison shows how a lower payment usually means a much higher total cost.

    Tips

    • Set up autopay: federal servicers take 0.25% off your rate.
    • Send extra payments with instructions to apply them to the highest-rate loan.
    • Check whether you qualify for an income-driven plan or PSLF before refinancing federal loans.

    Frequently asked questions

    How much is a $50,000 student loan per month?

    At 6.5% over 10 years, about $568 a month. Over 20 years it drops to about $373, but total interest roughly doubles.

    What is the standard repayment term for federal student loans?

    10 years with fixed monthly payments, or up to 30 years for Direct Consolidation Loans depending on the balance.

    Is it better to pay off student loans early?

    If there’s no prepayment penalty (federal loans never have one), extra payments reduce principal and total interest. Weigh it against higher-rate debt and retirement matching first.

    Does refinancing federal loans make sense?

    It can lower your rate, but refinancing into a private loan permanently gives up federal protections such as income-driven plans, deferment and forgiveness.

    How is student loan interest charged?

    Federal loans accrue simple daily interest on the principal. The monthly amortization used here gives nearly identical results for planning.

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    Sources