How is my monthly mortgage payment calculated?

Your monthly payment is calculated using the standard amortization formula: M = P × [r(1+r)^n] / [(1+r)^n − 1], where P is the loan principal, r is the monthly interest rate, and n is the number of payments. DIYLoanCalc computes this instantly as you adjust your inputs.

How much can I save with extra monthly payments?

Extra monthly payments go directly toward your principal, reducing the balance faster and cutting the total interest you pay. Use the Accelerate Payoff section in DIYLoanCalc to enter any extra monthly or annual amount and instantly see your interest savings and new payoff date.

What is an amortization schedule?

An amortization schedule shows every payment over the life of a loan broken down into principal and interest portions. Early payments are mostly interest; later payments are mostly principal. DIYLoanCalc shows a yearly breakdown you can expand to month-by-month detail and download as a CSV.

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Frequently Asked Questions

Everything you need to know about loan calculations, amortization, and making smarter borrowing decisions.

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Frequently Asked Questions