Enter balance, rate, remaining term, escrow, and a steady extra principal amount. See the required P&I, what actually leaves checking each month, and how far that extra slides the payoff date. Free, no sign-up.
This is payoff math on a loan you already have (or a quote you are pricing). It is not a rent-vs-buy comparison.
Assumes a fixed rate, no prepayment penalty, and that extra always goes to principal. Escrow amounts and lender rounding can differ from your statement.
Take a $320,000 balance at 6.5% with 30 years left and $450 escrow. Required P&I is about $2,023, so about $2,473 leaves checking. Add $200 extra principal each month.
The same loan, $200 more to principal each month, pulls the Mortgage Free date forward by about six and a half years and avoids roughly $105,000 of interest in this example.
Principal and interest use the standard fixed-rate formula from balance, annual rate, and remaining months. That is the loan payment before taxes and insurance.
Cash leaving monthly adds escrow (taxes and insurance) so you see the checking hit, not only the amortization line.
Extra principal is applied every month after interest. The calculator runs the schedule with and without that extra so you can see months pulled forward and interest avoided.
For a fixed-rate loan, monthly principal and interest is balance × r(1+r)^n ÷ ((1+r)^n − 1), where r is the monthly rate and n is remaining months. Taxes and insurance are separate escrow.
Usually no. Your scheduled P&I stays the same unless you refinance or recast. Extra principal shortens the remaining term and cuts total interest instead.
High-APR revolving debt usually costs more than a mortgage rate. Clear expensive cards before pouring surplus into a low-rate home loan, unless cash flow or peace of mind says otherwise. More in Snowball or avalanche for my debts?.
No. This tool moves a payoff pin on a loan you are modeling. Rent vs buy compares two housing paths over how long you stay. More in Rent vs buy as a projection.
Related reading: Extra principal moves the pin, Rent vs buy as a projection, The extra $200. More free calculators at theflan.app/tools.