Student loan calculator
See your monthly payment, total interest, and how extra payments shorten the loan.
Federal loans commonly use a 10-year standard plan. Check your loan servicer for your exact rate.
How the payment is calculated
Most student loans use a fixed monthly payment. The payment is set so that the balance reaches exactly zero at the end of the term. Early payments are mostly interest, and later ones are mostly principal, because interest is charged on whatever balance remains.
The power of extra payments
Any extra money sent to your servicer goes straight to principal, which lowers the balance that interest is charged on. Even a small amount each month can cut years off a loan and save hundreds or thousands of dollars. Confirm with your servicer that extra payments are applied to principal.
What this does not include
This is an estimate for a fixed-rate loan with a constant payment. It does not include interest that builds up while you are in school, deferment or forbearance, income-driven plans, or forgiveness programs. Check your loan servicer’s own tools for exact figures.
Worked example
A $30,000 loan at 5.5% interest repaid over 10 years has a monthly payment of $325.58. Over 120 payments you pay $39,069 in total, so $9,069 of it is interest.
Paying an extra $100 a month pays the loan off in about 7.2 years (86 payments) and cuts the total interest to about $6,316, saving roughly $2,750.
Frequently asked questions
How is the monthly payment calculated?
With the standard amortization formula: payment = P × r ÷ (1 − (1 + r)⁻ⁿ), where P is the amount borrowed, r is the monthly interest rate (annual rate ÷ 12) and n is the number of monthly payments.
Why does so much of each early payment go to interest?
Interest is charged on the remaining balance, which is largest at the start. As the balance shrinks, more of each payment goes to the principal.
Do extra payments really help?
Yes. Extra money goes straight to the principal, so the loan accrues less interest every month after that. Ask your servicer to apply extra payments to principal, not to future payments.
What doesn’t this include?
Federal loans may have income-driven plans, deferment, forgiveness programs and interest that builds up while you’re in school. This calculator shows a standard fixed-payment plan only.