Refinance Savings & Costs Calculator
Compare your current mortgage with a refinanced loan.
All calculations happen locally in your browser — nothing is uploaded, stored or tracked.
Enter your current mortgage
Balance, rate and years remaining.
Enter the new loan
Rate and term you are considering, plus costs.
Read the comparison
Monthly, lifetime and break-even.
What Is a Refinance Calculator?
A refinance replaces your current mortgage with a new one, usually at a lower rate. This calculator compares the two side by side: payments, total interest, the savings from refinancing and the break-even point given the closing costs.
It handles the real-world case where you have a remaining balance and remaining term — not a fresh loan — and lets you choose the new term, which may be shorter or longer.
The Comparison
Each loan is amortised over its remaining/selected term. Break-even = closing costs ÷ monthly payment savings.
Your data never leaves your device.
Every calculation on this site runs in your browser using vanilla JavaScript. Nothing is uploaded, stored or tracked.
- 100% local, client-side calculations
- No data stored on any server
- No tracking, no analytics, no ads scripts
- Works offline once loaded
Frequently Asked Questions
When does refinancing make sense?
When the new rate is meaningfully lower, you will stay in the home past the break-even point, and the new term does not silently extend your debt.
How much can I save by refinancing?
The calculator compares total interest on both loans — the difference is your lifetime saving.
What if I extend the term when refinancing?
Extending the term lowers the payment but can increase total interest even at a lower rate — the comparison makes this visible.
Are closing costs worth it?
Compare them against the break-even months: if you expect to stay longer than that, refinancing is likely worth it.
Does the calculator include taxes and insurance?
No — those are unaffected by refinancing and are excluded from the comparison.