Identify the loan principal (P)
Identify the annual interest rate (r) and convert to monthly rate: i = r / 12
Identify the loan term in years (Y) and convert to monthly payments: n = Y * 12
Use the mortgage payment formula:
M = P * [ i * (1 + i)^n ] / [ (1 + i)^n − 1 ]
If the interest rate is 0%, use:
M = P / n
Calculate total monthly cost if needed:
Total monthly = M + monthly property tax + monthly homeowners insurance + monthly HOA + monthly mortgage insurance (if applicable)
Calculate total amount paid over the loan term if needed:
Total paid = M * n
Calculate total interest paid if needed:
Total interest = (M * n) − P