A biweekly amortization schedule is a table that details your loan payments every two weeks instead of the traditional monthly payment schedule. The tutorial shows how to build an amortization schedule in Excel to detail periodic payments on an amortizing loan or mortgage.This spreadsheet creates an amortization schedule for a fixed-rate loan, with optional extra payments. Use this calculator to determine your payment or loan amount for different payment frequencies. Wrap Up. First… What is an Amortization Schedule in Excel? Definition: An amortization schedule is a tool for tracking loan payments over time. This calculator will help you figure out your regular loan payments and it will also create a detailed schedule of payments. This spreadsheet-based calculator creates an amortization schedule for a fixed-rate loan, with optional extra payments. Payments per year - defaults to 12 to calculate the monthly loan payment which amortizes over the specified period of years.