About AmortWise

AmortWise exists to make mortgage amortization math visible. Most borrowers know their monthly payment but have never seen how much of it is interest, when their balance actually hits zero, or what one extra payment a month does to a 30-year loan. The two calculators on this site — the biweekly mortgage calculator and the extra payment calculator — put those numbers on screen, computed with the standard amortization formula, with every figure explained in the surrounding text.

Our Mission

Provide free, transparent mortgage amortization tools. Transparent means the math is shown: the formulas are stated on each calculator page, worked examples use the same engine as the live calculators, and results never hide behind a "talk to an agent" wall. Free means no registration, no email gate, no trial, and no paid tier for the core tools.

Who Maintains It

AmortWise is maintained independently as a personal project. It has no affiliation with any lender, broker, or loan servicer, does not originate loans, and does not sell mortgage leads. The site is funded by the advertising you may see on its pages; that advertising is served by third parties and never influences calculator results — the same formula runs whether an ad shows or not.

How the Calculators Work

Both calculators use the standard fixed-rate amortization formula, M = P × r / (1 − (1 + r)⁻ⁿ), and simulate the loan payment by payment, month by month, applying extra amounts directly to principal. The biweekly calculator additionally models the 26-half-payments-per-year schedule. Nothing is fetched from a server when you calculate; your inputs stay in your browser. For the limits of these estimates — taxes, insurance, and fees are not modeled — see the terms of use.

Contact

Corrections, bug reports, and suggestions are welcome. Reach the maintainer through the contact page. Data handling is described in the privacy policy.