Mortgage & Real Estate
Home shopping, refinancing, or mapping your payoff strategy — run the numbers here. For the full story on why mortgage interest works the way it does, see the link below.
Bank calculators disclose what the law requires. This calculator shows what the law doesn’t require them to tell you — including why 85% of your first year’s payments go to interest, not to owning more of your home.
See the full picture →Enter a list price and down payment — as a percentage or a dollar amount — and the calculator sets the loan amount automatically. Adjust rate and term to compare scenarios before you make an offer.
Switch to refinance mode, enter your current balance, your existing rate, a proposed new rate, and estimated closing costs. The calculator shows your monthly savings, total interest saved over the remaining term, and the break-even point — how many months until the closing costs pay for themselves. If you plan to stay in the home beyond that point, the refinance saves money. If not, it may not.
Recast vs. refinance: If you have a lump sum available and your current rate is competitive, recasting is almost always cheaper than refinancing. No appraisal, no title insurance, no new origination — just a $150 to $500 fee and a lower monthly payment. Call your servicer and ask: "Do you offer mortgage recasting?" Most do. Few volunteer it.
Use the extra monthly payment and lump sum fields to model what happens when you put more toward principal. The amortization table shows exactly how much each payment shifts the interest/principal split, and the payoff banner shows how many months and dollars you save.
No appraisal. No title work. No new origination. Rate and term stay the same. Monthly payment drops after lump-sum principal reduction.
Full underwriting process. Resets amortization to month one. Only pencils out with meaningful rate reduction and enough remaining time in the home to pass the break-even point.
The HELOC caution: Borrow against equity to pay off credit cards → spend back up on credit cards → equity is consumed and consumer debt is back. This is one of the most common and most destructive patterns in personal finance. Equity is not a revolving credit account.
About the Author
James is a certified financial coach and the founder of DebtInterestCalculator.com. Having bought and sold multiple homes, financed more than a few cars, and spent years wondering why the numbers never seemed to add up, he built this site to share what he wishes someone had shown him sooner. His mission is simple: help everyday people understand the real cost of borrowing — and the real power of knowing the rules.
For educational purposes only. Results are estimates based on the inputs you provide. Does not constitute financial advice — consult a qualified professional before making borrowing decisions.
See every loan you carry, the total annual interest burden across all of them, and a unified payoff plan — all in one place.
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