Loan Parameters
Range 1,000 - 100,000,000
Range 1 - 50
Range 0 - 20, 0 = interest-free
Added to monthly payment
Homeowner's insurance per year
Additional principal each month
Calculation Results
Equal Payment vs Equal Principal
Visualizations
Payment Composition (Principal / Interest)
Remaining Balance Curve
Amortization Schedule
| Period | Payment ($) | Principal ($) | Interest ($) | Balance ($) |
|---|
View Calculation Formula
Equal Payment: Monthly M = P·r·(1+r)n / ((1+r)n − 1), r = annual rate/12, n = term×12; total interest = M·n − P.
Equal Principal: Month k = P/n + (P − (k−1)·P/n)·r; total interest = (n+1)·P·r/2.
Monthly payment with taxes and insurance = M + (property tax + insurance) / 12.
Extra payment reduces principal each month, shortening the term.
Amounts use integer cents internally to avoid floating-point errors.