What Is a Loan & Mortgage Calculator?
The Loan & Mortgage Calculator shows the fixed monthly payment for a loan, how much interest you pay in total, and a year-by-year amortization schedule.
A loan calculator works out the fixed monthly payment for an amortising loan — a mortgage, car loan or personal loan — along with the total interest you will pay and a schedule showing how the balance falls over time. It turns the three numbers you know (amount borrowed, interest rate and term) into the one number you really need: what it costs each month, and overall.
How to Use the Calculator
- Enter the loan amount (the principal you borrow).
- Set the annual interest rate and the term in years or months.
- Read the monthly payment, total interest and the yearly amortization table.
Use Cases: Who Needs a Loan Calculator?
- Home buyers comparing mortgage offers and checking what monthly payment fits their budget.
- Car buyers and borrowers weighing the true cost of a loan before signing.
- Anyone deciding between a shorter term with higher payments and a longer one with more total interest.
- People planning extra payments and wanting to see how much interest they could save.
How the Monthly Payment Is Calculated
The fixed payment comes from the amortisation formula M = P × r × (1 + r)^n ÷ ((1 + r)^n − 1), where P is the loan amount, r the monthly interest rate (the annual rate divided by 12) and n the number of monthly payments. Each month part of the payment covers interest on the remaining balance and the rest reduces the principal.
Early on, most of each payment goes to interest because the balance is large; as the balance shrinks, more of every payment chips away at the principal. The amortisation schedule lays this out period by period, which is why the total interest can be a surprisingly large share of the loan over a long term.
Benefits and Use Cases
- Compare mortgages, car loans or personal loans before you commit.
- See how the rate and term change your total interest.
- Runs entirely in your browser — your figures stay private.
Privacy First: Why Use Fastway Tools?
All the calculations run in your browser. The loan figures you enter are never uploaded, logged or stored on our servers — the maths happens in client-side JavaScript on your own device. That keeps your financial details private and the calculator instant and usable offline once the page has loaded.