Loan calculator
Compare fixed and SAC schedules with a balance chart and interest split.
100% in browser — No files or data are sent to a server. Everything runs on your device.
Simulate a loan with amount, annual rate and term. Choose Price (fixed installment) or SAC (constant amortization, declining payment — common in Brazilian mortgages).
The donut shows how much of the total paid is principal versus interest. The chart tracks remaining balance year by year, and the table summarizes cumulative amortization.
The rate is a nominal annual figure divided by 12. The math runs in your browser and excludes insurance, taxes and fees.
Frequently asked questions
What is the difference between Price and SAC?
Price keeps the installment constant. SAC keeps amortization constant, so the payment starts higher and falls over time.
Does the rate include all costs?
No. Enter the contractual interest rate. Extra charges are out of scope.
Is my data sent to a server?
No. Everything is calculated locally.
Does this replace a bank quote?
No. It is an educational estimate, not a credit offer.