Most homeowners know that paying a little extra toward their mortgage each month saves money. What's harder to know is how much — and that's exactly what this calculator shows you.
Enter your loan amount, interest rate, and term, then add whatever extra amount you're considering putting toward principal each month. The calculator instantly shows two things side by side: your standard payoff timeline, and what happens when that extra payment gets applied every month for the life of the loan.
The math behind it is straightforward but easy to get wrong by hand. Extra payments go entirely toward principal, which means every dollar you add early shrinks the balance that future interest gets calculated on. That compounding effect is why even a modest $100–$200 extra payment can shave years off a 30-year loan and save tens of thousands in interest — the timeline above makes that gap visible at a glance instead of buried in a spreadsheet.
There's no signup, no email required, and nothing is sent to a server — every calculation happens right in your browser, so you can adjust the numbers as many times as you want and see the results update instantly.
Whether you're deciding if refinancing makes sense, weighing an extra payment against other savings goals, or just curious how close you could get to mortgage-free, this tool gives you a real answer in seconds.