Refinance breakeven
See exactly when a refinance pays for itself, what it saves you each month, and whether restarting the clock actually costs more in the long run.
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How this is calculated
Both payments use the standard amortization formula: M = P × [r(1+r)ⁿ] / [(1+r)ⁿ − 1], with r = rate ÷ 12 and n = term × 12. Monthly savings is simply the current payment minus the new one. Breakeven months is closing costs ÷ monthly savings, rounded up to the next whole month. The lifetime line compares the total remaining cost on your current loan (current payment × remaining months) against the total cost of the new loan (new payment × new term + closing costs). Note the trap: refinancing to a lower rate but restarting a fresh 30-year clock can leave you paying more in total interest than the loan you already have, even while your monthly payment drops. Always check the lifetime row.
About closing costs
Refinance closing costs typically run 2–6% of the loan amount — appraisal, title, origination, and lender fees. A low breakeven only matters if you actually stay in the home past it. If you might move, get transferred, or refinance again within the breakeven window, the math flips even on a rate that looks like an obvious win.