Google Analytics allows you to create numerous filters. So how do you know which ones you need to implement for your site? Well, one you might want to explore is a lowercase filter. So what is a lowercase filter and what precisely does it do?
Lowercase filters change the selected field to all lowercase letters. If duplicate entries of the same page are appearing in your reports, one that contains uppercase letters and one that does not, you probably should set your lowercase filter. For example, if you have a page on your site that can be accessed by going to www.mysite.com/Products.htm but you could also access the same page by typing www.mysite.com/products.htm Google Analytics would track these as two separate pages.
Obviously, if these are the same page they should be tracked as a single entry in Google Analytics. Therefore, creating a lowercase filter will change the former URI to all lowercase letters. This can greatly affect your Google Analytics reports and prevent duplicate entries from appearing.
So how do you set up a lowercase filter?
Within Google Analytics on the Add Filter to Profile page select the filter type Custom. Then Click the radio button next to the lowercase filter. Select the filter field that you want to apply the lowercase filter to and click Finish. Your new lowercase filter has been applied! NOTE: This will only affect the data from this point forward, not the historical data that has already been collected. Your filtered results will begin to show up in the reports from this point forward.
So in the above example the lowercase filter was applied to the request URI but you can apply the lowercase filter to other fields. If you apply the filter to the Campaign Term field it will prevent, for example Cars, cars, and CARS from showing up as different fields within the keyword reports. You can also apply the lowercase filter to the User Defined Value to prevent duplicate entries with those as well.
Hopefully this has given you a quick insight into lowercase filters and how useful they can be for your site.