Principal
Principal is the original amount you borrow or invest, separate from the interest on it. On a loan, each payment splits between interest (the cost of borrowing) and principal (which actually shrinks the debt) — and early on, most of a mortgage payment goes to interest.
Paying extra directly toward principal shortens the loan and cuts total interest, because future interest is charged on a smaller balance. An amortization schedule shows exactly how the principal-versus-interest split shifts toward principal over the life of the loan.
Put it to work
Mortgage Calculator
Estimate your monthly mortgage payment with taxes, insurance, PMI and HOA — plus total interest and a full amortization breakdown. Free, fast, no signup.
Amortization Calculator
Build a complete amortization schedule for any loan: payment, year-by-year principal vs interest split, and the effect of extra payments.
Loan Calculator
Calculate the monthly payment, total interest, and payoff date for any personal, auto, or fixed-rate loan — and see how extra payments shorten it.