Student Loan Calculator
Monthly payment, total interest, and payoff time with extra payments
Use this when you need a fast, accurate result — no sign-up, works entirely in your browser.
Monthly payment—
Total interest—
Payoff time (months)—
Interest saved with extra payment—
How to Use
- Enter your details into the fields above.
- Click the calculate button to get your result instantly.
- Use the clear button to start a new calculation.
Example
- $30,000 balance, 6.5% APR, 10 years, +$100/mo extra → Monthly $340.64; total interest $10,877.27; payoff 86 months; saves $3,347.15
- $40k loan, 5.5%, 10-yr plan, +$200/mo extra → Standard $434.11/mo → paid off in 75 months, save ≈ $4,772 interest
Formula
Monthly payment = P × r × (1+r)n / ((1+r)n − 1), with r = APR/12 and n = months. Payoff time solves n = −ln(1 − Br/M) / ln(1+r) where M includes any extra payment. Extra payments cut interest because they reduce principal earlier.
About Student Loan Calculator
Monthly payment, total interest, and payoff time with extra payments. This free online tool gives you fast, accurate results without registration or downloads.
Everything runs locally in your browser, so your data is never uploaded or stored — privacy first.
Frequently Asked Questions
Is this tool free to use? +
Yes, it is completely free with no registration or download required.
Is my data private? +
Yes. Everything is processed locally in your browser. Nothing is uploaded or stored on our servers.
Does it work on mobile? +
Yes, it works on any device — phone, tablet, or desktop.