Student Loan Payoff Calculator

What this calculator tells you

You have a balance, you are making a monthly payment, and somewhere in the back of your mind sits the real question: when does this end, and how much will it cost me to get there? This calculator answers both. From your balance, your monthly payment, and your interest rate, it works out how long until the loan is gone, the total interest you will pay, and a payoff date to circle on the calendar.

How to use the Student Loan Payoff Calculator

• Loan Balance: what you currently owe.
• Monthly Payment: what you pay each month.
• Interest Rate: your annual rate, as a percentage.

Press Calculate, and you get the time to pay off, the payoff date, the total interest, and the total you will pay.

How the Student Loan Payoff Calculator works

Each month, part of your payment covers the interest on what you still owe, and the rest chips away at the balance. The calculator runs that forward to find how many payments it takes to reach zero:

Months to pay off = ln(payment ÷ (payment - balance × monthly rate)) ÷ ln(1 + monthly rate)

where the monthly rate is your annual rate divided by 12. There is one catch hiding in that formula, and it matters: your payment has to be larger than one month's interest. If it is not, the balance never shrinks, the loan never pays off, and the calculator will tell you the numbers do not work. That is not a glitch, it is the math warning you that you are only treading water.

A worked example

Say you owe $30,000, pay $400 a month, at 6%.

One month's interest at the start is $30,000 × 0.005 = $150, so of your first $400, about $150 covers interest and $250 goes to the balance. Run that forward and the loan is paid off in about 94 months, roughly 7 years and 10 months. You would pay about $37,694 in total, of which around $7,694 is interest.

The power of paying a little more

Here is the most useful thing this tool can show you. Because interest is charged on what you still owe, every extra dollar you put on the balance saves you interest on all the months that follow. So a small bump in your payment pays off twice, in time and in money.

Take the same $30,000 loan at 6%. Paying $400 a month clears it in about 94 months. Bump that to $500 a month, and it is gone in about 71 months, nearly two years sooner, with roughly $1,900 less interest paid. That is the whole case for throwing a bonus, a tax refund, or a raise straight at the principal: the loan shrinks faster and costs less.

What this does not model

This is a clean estimate, and real student loans have a few wrinkles it does not capture:

• It assumes a fixed rate and a steady payment. Variable-rate loans and changing payments will land differently.
• Capitalization is not modeled. If unpaid interest has already been added to your balance during school, grace, or forbearance, your real starting point and cost may be higher.
• Income-driven plans work differently. Federal income-driven repayment sets payments from your income and can stretch or forgive the balance, which this does not reflect.
• Tell your servicer where extra payments go. A bigger payment only speeds things up if it lands on the principal. Some servicers apply it to next month's bill unless you ask.

Who this is for

• Borrowers in repayment who want a real payoff date instead of a vague "someday."
• Anyone thinking about paying extra, who wants to see exactly how much time and interest a bigger payment saves.
• Budgeters weighing a faster payoff against other goals.

Working it the other way, starting from a loan term to find the monthly payment, is the Student Loan Calculator. To weigh the degree against its cost in the first place, see the College Value Calculator.

Things to keep in mind

• This is an estimate, not financial advice. For decisions about repayment plans, refinancing, or forgiveness, your servicer and a qualified advisor know your full situation.
• Your payment must beat the monthly interest. If it does not, the balance will not fall, no matter how long you keep paying. Raising the payment even a little can flip that.
• For exact federal figures, use the official tools. The Federal Student Aid Loan Simulator, linked below, models plan types and capitalization that a simple calculator cannot.
• Most student loans have no prepayment penalty. Paying extra is almost always allowed and almost always smart, but confirm with your servicer and ask that it go to principal.

Questions people ask

References

1. Federal Student Aid, U.S. Department of Education. Loan Simulator. https://studentaid.gov/loan-simulator/
2. Federal Student Aid, U.S. Department of Education. Understand how interest is calculated and what fees are associated with your federal student loan. https://studentaid.gov/understand-aid/types/loans/interest-rates
3. Consumer Financial Protection Bureau. Paying for college: student loans. https://www.consumerfinance.gov/paying-for-college/