Regular expressions, or “regex”, can be very useful within Google Analyitcs, but regex syntax is quite challenging, even for the initiated. Before your deploy your regular expressions, you should take advantage of tools that are designed specifically for regex testing.
As a simple example, let’s say that you have individual signup forms for eight different product trials on your website, and that the request URI of each thank-you page is in the following format:
Let’s also say that you want to set up a single signup goal for products 2 and 7, which are closely related.
Regexpal indicates a match, but when you also notice that it has highlighted the . character in the regex field, you realize that you have forgotten to “escape” the . character with a \ character to make it a literal . and not the regex notation for any single character. You just add \ before . to escape it.
Now you have a clean regular expression that will do its job for you as the Goal URL. (Just make sure that you select Regular Expression as your goal Match Type.)