Tracking Conversions

You've spent your advertising money, and you're getting traffic to your website. The big question is: "Are they buying or browsing?". You could ask customers who purchase to fill in a form about where they heard about the product, but the customer won't necessarily remember, or give you a straight answer. You probably won't be able to track all of your advertising either.

Is There a Better Way?

Yes, the simplest thing you can do is examine your web logs on your site. We did this for a long time, when we first started advertising with Google AdWords. We found that we were getting a lot of people who came to our site, but didn't actually get as far as downloading the trial versions of the program. Maybe they were coming back later--some were setting bookmarks, but it wasn't really possible to tell. Nevertheless, examining web logs is a useful exercise in any case.

There are many tools availble to let you examine your web logs. You can download a trial version of Wieser Software Ltd's program Top Drop from their website by clicking the link above. This program lets you quickly examine your web logs, and see where the visitors to your site are going. It also allows gives you other useful features at the click of a button.

How Can I Take the Next Step?

We decided that the best way to track real conversions to actual sales was to write a cookie to the user's machine when they first come to the site. Then, it sits there, waiting. When the user actually purchases the product they saw advertised, we read the cookie, and pass it along with the order data. If the sale completes, we know the advertising worked.

Caveat: Some users disable cookies and scripting on their machines. When they do this, they effectively block any tracking.

How do I Write a Cookie to a User's Machine?

It turns out that when you type in the address of a website, the text the customer typed into the browser is available to the web page. It also so happens, that you can pass additional information at the end of an address to most web servers by putting it after a question mark. So for instance, the Wieser Software Ltd. product "RIP Vinyl" could have a link like this passed to it:
http://www.ripvinyl.com?sawyourad

The web page that is loaded as the index page contains the following code:

                    <script type="text/javascript">

                    <!--

                    var curloc = document.location+"";

                    var idx = curloc.indexOf("?");

                    if (idx > -1)

                    {

                        var affil = curloc.substring(idx+1);

                        var expireDate = new Date();

                        expireDate.setDate(30 + expireDate.getDate());

                        if (""==document.cookie)

                        {

                           document.cookie = "a="+affil+"; expires="+
                    expireDate.toGMTString() + ";"

                        }

                    }

                    //-->

                    </script>

This code strips off everything after the question mark character in the URL and sets it as a cookie named "a" that expires in 30 days time. If there is already a cookie set for this page, then it is left as it was. This allows us to find out how the user first heard about us.

Remember, you can change the expiry date to suit your own needs.

Reading the Cookie at the time of purchase

Cookies are stored on the users site, associated with a particular directory on their website. So for instance, www.wieser-software.com/qualtime cookies are distinct from www.wieser-software.com/tables cookies. This provides some security to users, as a web page can only read cookies in the same subdirectory as the web page itself.

To read a cookie, read add the following code to your conversion page(s):

            <script type="text/javascript">

            <!--

                var affil = document.cookie;

                if (""==affil)

                {

                   affil = "a=(NULL)";

                }

            //-->

            </script>

You can then use the value of the variable affil anywhere else on your page, building it into the purchase code for example on your website. You could also use it to offer the user a discounted price, that matches the one in your advertisement.

Get Tracking

We hope that this article will give you a feel for how you can use cookies to track conversions to sales. If you don't manage your own website we offer consulting services, and will help you get this working for your system. Otherwise, the people running your website should be able to understand the technical details shown here.

Anthony Wieser
Founder of SawYourAd.com