Loans & Refinance Calculators

These calculators answer three questions about a loan you already have or are about to sign: what the repayment schedule actually looks like, what prepaying it saves, and when refinancing it pays for itself. All three are amortization problems. Every fixed-rate installment loan — auto, student, personal, or mortgage — splits each payment between interest on the current balance and principal reduction, so each question has an exact answer that comes from rebuilding the payment schedule rather than from rules of thumb.

The refinance break-even tool exists because a refinance is a purchase: you pay closing costs today in exchange for a lower rate or payment. Dividing the closing costs by the monthly payment reduction gives the break-even point — the number of months until the refinance has recouped its own cost. The tool computes that, and also the number a payment-only comparison hides: net lifetime savings. A lower monthly payment stretched across a reset, longer term can cost more total interest than the loan it replaced, so the tool reports the monthly saving and the lifetime difference separately, including the effect of restarting the clock on a fresh term.

The other two tools work the loan as it stands. The amortization schedule calculator is the foundation: enter amount, rate, and term and it builds the full table — the fixed payment, a year-by-year principal and interest breakdown, and the complete monthly schedule with the balance at every point. The extra-payment tool is the prepayment counterpart, and it works on any amortizing loan, not just mortgages: add a recurring extra amount or a one-time lump sum and it returns the new payoff date, the interest saved, and the revised schedule. The division of labor is simple: the schedule tool shows the loan as written, extra payments show what accelerating it is worth, and break-even weighs a rate quote against its closing costs. The table below summarizes the split.