Refinance Calculator
Compare current mortgage vs. refinance.
Inputs
$
%
yrs
%
yrs
$
Result
Current Payment$1,847.48
New Payment$1,458.93
Monthly Savings$388.55
Total Interest Saved$29,027.81
Break-Even on Fees10.3 months
About the Refinance Calculator
The Refinance Calculator compares your existing mortgage to a proposed refinance, showing the new monthly payment, monthly savings, and the number of months needed to recover closing costs (the break-even point).
Calculation method
It amortizes both loans and computes break-even = closing costs ÷ monthly savings. Refinancing makes sense when you'll stay in the home past the break-even point.
New payment = amortized(Balance + Costs, New rate, New term)
Break-even months = Closing costs / (Old payment − New payment)How to use this calculator
- Enter your current balance, rate, and remaining term.
- Enter the new rate, new term, and expected closing costs.
- Compare payments and check the break-even in months.
Example
Refinancing a $250,000 balance from 7.5% (25 years left) to 5.75% (new 30-year loan) with $4,000 in costs drops the payment by roughly $335 per month and breaks even in about 12 months.
Frequently asked questions
When is refinancing worth it?
When the rate drops enough that savings recover the closing costs before you move or refinance again. A common rule of thumb is a rate drop of at least 0.75%.
Should I roll closing costs into the loan?
Rolling costs in avoids out-of-pocket cash but grows the balance and slightly raises the payment. This calculator assumes costs are financed with the new loan.
Does refinancing reset the loan?
Yes. A new 30-year loan restarts amortization. To avoid paying more interest over time, choose a term equal to or shorter than what remains on the current loan.
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.