Finding software tools to gauge data storage requirements

When deploying a new disk backup appliance are there software tools available to help determine what capacity you will need now and going forward based on factors such as retention time, data growth, etc.?

There doesn't seem to be universal tool for estimating data storage requirements. Different types of data grow at different rates and often have differing retention requirements. It is best to calculate data storage requirements on a per-data-type basis.

For example, Microsoft offers a tool called the Exchange 2010 Mailbox Server Role Requirements calculator. This tool estimates Exchange Server's data storage requirements based on factors such as the volume of mail that users send and receive on a daily basis and average attachment sizes.