See what your mortgage actually costs you.
Enter your loan details below. The calculator shows your current payoff timeline alongside faster scenarios — with exact interest figures for each.
Earlier dollars eliminate more interest
$100/month extra from year one
Same $100 starting year ten
One lump sum, visible impact
A single $5,000 principal payment in year two can save more in total interest than the same amount applied in year fifteen. The calculator shows you the exact figure.
On a typical 30-year mortgage, an extra $100 starting in month one can cut over four years off the term and eliminate more than $28,000 in interest.
The same extra payment begun a decade later saves roughly half as much interest. The payoff arc is non-linear — waiting has a measurable, specific price.
All projections use standard amortization math: each month's interest is calculated on the remaining principal balance, so extra payments reduce the base the next month's interest is charged against.
Figures shown are illustrative estimates. This tool does not account for escrow, PMI, tax implications, or prepayment penalties. Verify details with your lender before making changes to your payment schedule.