Loan Calculator
General-purpose calculator for amortized loan payments and totals.
Inputs
$
%
years
Result
Monthly Payment$1,264.14
Total Interest$255,088.98
Total Paid$455,088.98
About the Loan Calculator
The Loan Calculator estimates monthly payments and total interest for any amortizing loan — personal, auto, student, or small business — from the amount, rate, and term.
Calculation method
Standard amortizing-loan formula. Every payment covers interest on the current balance plus a principal portion; the principal share grows over time.
M = P × r × (1 + r)^n / ((1 + r)^n − 1)How to use this calculator
- Enter the loan amount.
- Enter the annual interest rate.
- Enter the term in years.
Example
A $25,000 loan at 8% for 5 years has a $506.91 payment and $5,415 in total interest.
Frequently asked questions
What is APR?
The annualized cost of borrowing including interest and most fees. APR is a better comparison than nominal rate when loans have different fee structures.
Fixed vs. variable rate?
Fixed locks the rate for the life of the loan. Variable can start lower but change with market rates, raising the payment.
How is a longer term riskier?
It lowers the payment but greatly increases total interest paid over the loan's life.
Student loans: what to know before you calculate
Student loans are amortizing installment loans — the same math as auto and personal loans — but the terms, rates, and repayment plans are unique. US federal loans have fixed rates set each July, standard 10-year terms, and income-driven options. Private loans price on credit and can be fixed or variable. Whichever type you have, the monthly payment depends on three inputs: balance, interest rate, and term.
Worked examples
- Undergraduate — $27,000 federal
$27,000 balance at 6.53% on the Standard 10-year plan = about $307/month, with roughly $9,850 total interest over the life of the loan.
- Graduate — $60,000 federal
$60,000 balance at 8.08% on a 10-year term = about $730/month, with roughly $27,600 total interest paid.
- Refinance — $45,000 private
Refinancing $45,000 from 7.5% to 5.75% over 10 years drops the payment from $534 to $493 and saves close to $5,000 in interest — if you don't need federal protections.
Student loan FAQs
How is a student loan monthly payment calculated?
Student loans use the standard amortizing-loan formula: M = P × r × (1 + r)^n / ((1 + r)^n − 1), where P is the balance, r is the monthly interest rate (APR ÷ 12), and n is the number of months. Federal loans typically use a 10-year (120-month) standard term.
What is a realistic interest rate for student loans?
US federal undergraduate Direct loans for 2024–25 are 6.53% fixed, graduate Direct loans 8.08%, and PLUS loans 9.08%. Private student loan rates typically range from 4% to 15% depending on credit and whether you choose fixed or variable.
Standard vs. income-driven repayment — which saves more?
The Standard 10-year plan has the highest monthly payment but the lowest total interest. Income-driven plans (SAVE, IBR, PAYE) lower payments based on income but extend the term to 20–25 years, so total interest paid is usually much higher unless forgiveness applies.
Should I refinance federal student loans?
Refinancing to a private lender can reduce your rate if you have strong credit and stable income, but it permanently forfeits federal benefits: income-driven plans, deferment, forbearance, and Public Service Loan Forgiveness (PSLF). Only refinance federal loans if you're certain you won't need those protections.
Do extra payments really shorten a student loan?
Yes. Every extra dollar goes to principal, which lowers the balance interest is charged on next month. Just $50 extra per month on a $30,000 loan at 6% over 10 years pays it off about 18 months early and saves roughly $1,600 in interest.
Ready to run the numbers?
Use the dedicated Student Loan Calculator to see your monthly payment and total interest.
Disclaimer: This calculator is for informational and educational purposes only and does not constitute financial, tax, or legal advice. Consult a qualified professional for decisions specific to your situation.