This is an Excel based retirement savings calculator. Download the Excel template from the link below and start using it. It requires entering your current age, retirement age, investments up to now, expected annual return, annual payments and number of remaining payments. It will calculate your annual and cumulative interest earned, and total balance by year. It will also create a chart of your retirement balance, payments, and interest by years. 

How to Turn Excel Templates into Web Applications

You can turn this or any Excel file into a web application with SpreadsheetWeb. Delivering it as a web application helps protect your data and business logic. Your users can still access parts of your file, enter data and see the calculation results. But they won't be able to see the actual formulas nor modify them. Delivering your Excel file as a web application will allow many users accessing it at the same time while protecting their data. They cannot see each others data. Their data is fully protected.

The web application created from this Excel template is below: