Calculate your monthly mortgage payment using the standard amortization formula.
A mortgage calculator estimates your monthly home loan payment based on the loan amount, interest rate, and loan term. The formula used is:
Where P = principal loan amount, r = monthly interest rate (annual rate ÷ 12), n = total number of monthly payments. For example, a $280,000 mortgage at 6.5% over 30 years results in a monthly payment of approximately $1,771.
A mortgage payment is calculated using the formula M = P[r(1+r)^n]/[(1+r)^n-1], where M is the monthly payment, P is the principal loan amount, r is the monthly interest rate (annual rate divided by 12), and n is the total number of payments (loan term in years multiplied by 12).
As of 2026, average 30-year fixed mortgage rates are approximately 6.5-7.0%. Rates vary based on credit score, loan type, and down payment amount.
A common guideline is the 28/36 rule: your mortgage payment should not exceed 28% of gross monthly income ($1,750/month on $75K). At 6.5% for 30 years, this supports approximately a $275,000 home with 20% down.
A fixed-rate mortgage keeps the same interest rate for the entire loan term, providing predictable payments. An adjustable-rate mortgage (ARM) has a rate that changes periodically after an initial fixed period, which can result in lower initial payments but carries rate risk.