Financial Calculators / Free Tools
Free Student Loan Calculator Online
Use these free student loan calculators to work out your monthly payment, total interest, and how much faster you could pay off your loan with extra payments. Enter your numbers below - no sign-up required.
Simple Student Loan Calculator
Enter any three values and leave the field you want to solve for empty.
Student Loan Repayment Calculator
See how extra payments shorten your payoff time and reduce total interest, compared to your normal schedule.
Extra payments (optional)
What is a student loan calculator and why it matters
A student loan calculator works out the relationship between your loan balance, interest rate, monthly payment, and repayment term. Since these four numbers are all connected mathematically, knowing any three lets you solve for the fourth - useful for figuring out what payment you can afford, how long payoff will realistically take, or what rate you're effectively paying. A repayment calculator goes a step further and shows how adding extra payments on top of your normal payment shortens your loan and cuts the interest you'll pay overall.
How these calculators work
The simple calculator uses the standard loan amortization formula that relates loan balance, interest rate, term, and payment. Leave any one of the four fields blank and the calculator solves for it using the other three - for the interest rate specifically, since there's no simple formula to isolate it directly, the calculator finds it through iterative approximation. The repayment calculator simulates your loan month by month, applying your regular payment plus any extra monthly, yearly, or one-time payments you specify, and compares the result against your original no-extra-payments schedule.
Common searches these calculators answer
- What will my monthly student loan payment be?
- How much interest will I pay over the life of my student loan?
- How much faster can I pay off my student loan with extra payments?
- How much interest do extra payments save on a student loan?
- What loan term do I need for a specific monthly payment?
How to use them
- Simple calculator: enter any three of loan balance, term, interest rate, and monthly payment, leaving the one you want solved blank, then click Calculate.
- Repayment calculator: enter your loan balance, current monthly payment, and interest rate. Optionally add an extra monthly amount, extra yearly amount, or a one-time extra payment.
- Click Calculate repayment to compare your payoff time and interest with and without the extra payments.
Tips
- Even a modest extra monthly payment can cut years off a 10-year student loan term, since extra payments reduce principal directly rather than just covering more interest.
- Check whether your loan servicer applies extra payments to principal by default - some require you to specifically request this, or extra payments may just prepay future installments instead.
- Federal subsidized loans don't accrue interest while you're in school, which the simple calculator here does not model - use it for the repayment phase once your loan term has started.
- Refinancing to a lower rate and making extra payments are two separate ways to reduce total interest - this repayment calculator only models the extra payment side.
Frequently asked questions
Are these student loan calculators free to use?
Yes. They are completely free, work in your browser, and do not require any sign-up or download.
Why do I need to leave a field blank in the simple calculator?
The four values - balance, term, rate, and payment - are mathematically linked, so only three independent values are needed. Leaving one blank tells the calculator which one to solve for.
Does the repayment calculator account for federal income-driven repayment plans?
No. It models a standard fixed-payment amortizing loan. Income-driven plans, which base payments on income rather than a fixed schedule, work differently and aren't reflected here.
What happens if my extra payments pay off the loan in the first year?
The calculator stops adding further payments once the balance reaches zero, so total interest and payments only reflect the months actually needed to pay it off.
Can I use this for other types of installment loans, not just student loans?
Yes. The underlying math is standard loan amortization, so it works for any fixed-rate installment loan such as a personal loan or auto loan.
