Student loan calculator

What this calculator models

It models a fixed-rate loan repaid in equal monthly installments, like the standard ten-year federal plan or most private student loans. Income-driven, graduated and extended plans change your payment over time and are not modeled here, so use your servicer’s tools for those.

Interest on unsubsidized and private loans can accrue while you are in school or in deferment and may be added to the balance when repayment starts. If you have that situation, enter the balance you will owe at the start of repayment.

Paying less interest on student loans

Pay interest while in school if you can, target the highest-rate loan with any extra money and confirm extra payments go to principal. Refinancing federal loans into a private loan can lower the rate but forfeits federal protections such as income-driven repayment and forgiveness programs, so weigh that carefully before you refinance.

$35,000 at 6.5% by loan length

Borrowing $35,000 at 6.5% over 10 years costs $397.42 a month and $12,690 in interest, $47,690 in total. Shorter terms raise the payment but cut the interest, and longer terms do the reverse. The table shows the trade-off across common terms.

How your rate changes the cost

Personal loan rates vary widely with credit score, from the mid single digits for strong borrowers to 30% or more for weak credit. On $35,000 over 10 years, moving from 6.5% to 9.5% adds $6,657 in interest.

How much can you borrow for a given payment?

Working backwards at 6.5% over 10 years, here is the loan size each monthly payment supports.

When is half of a $35,000 loan repaid?

With a $397.42 payment, the balance falls below half ($17,500) after 70 payments, about 5.8 years into a 10 years loan. Because interest is highest at the start, the second half of the loan is paid down much faster than the first.