In your spreadsheet, set up columns to organize and calculate each payment's details. Create a loan amortization calculator in Excel.You will create an amortization schedule for Loan Option 3 in cells C12:F35. All payments are end-of-the-period payments. The tutorial shows how to build an amortization schedule in Excel to detail periodic payments on an amortizing loan or mortgage. Choose interest only to make interest only payments. Create an amortization schedule for Loan Option 2 in cells C12:F71. All payments are end-of-the-period payments. Amortization schedule. Include comments and an amortization schedule from the lender if the payments are not based on standard amortization.