Email marketing continues to be an important way to advertise the products or services of your website. In order to judge the effectiveness of your campaign, however, it helps to find out how many of those emails were actually read and who read them. One of the easiest ways to do this is by inserting a tracking pixel into each of those emails.

Gauge Consumer Interest with Pixels

A tracking pixel, also known as a Web bug or Web beacon, is a small transparent image that is inserted into an email or Web page. When sent in an email, the link to the image can include the customer's email address and other information, such as an ID number for a cookie. When the customer reads the email, his IP address, email address and cookie ID will be sent to your Web server, as well as other information, such as the date, time and browser type. This data lets you know that that individual customer read the email and it also confirms that customer's unique IP address. Combined with the cookie, the IP address allows you to identify the customer on later visits to your site, showing which products seemed to interest him or her the most. Any purchases by that customer allow you to link his or her real name and address to his or her account. All of this data can allow you to customize your marketing techniques to better appeal to that customer's interests.

Creating the Invisible Image

To create the tracking pixel, open an image editor such as Photoshop, Paint Shop Pro or GIMP. From the file menu, choose to create a new image. Set the size of the image to one pixel wide and one pixel high. In the “Background” or “Fill” section, choose “Transparent.” Save your file with an appropriate name, such as “WinterSavings,” and select GIF as the format, since it preserves transparency. To track several mailings, rename the file for different events, such as “WinterSavingsDecember2013.gif” and “WinterSavingsJanuary2014.gif,” for December and January sales respectively. Place the files into an appropriate directory on your Web server.

Coding and Deploying the Tracker

Create a new email that includes your marketing materials. Place the image in a convenient location, such as at the bottom of the message, by using the email program's image-insert function, as long as you can insert a Web address as the location. Otherwise, use a standard HTML image tag with the address of your image:

<img src=”http://www.example.com/email/WinterSavingsDecember2013.gif?email=johndoe@example.com&ID=x55431111”>

The information after the question mark, the email address and cookie ID, is seen by the server and recorded in the log.

Analyzing the Results

The server logs will list the customers who have shown enough interest in your product to open the email and possibly visit your site. Future marketing campaigns can then be used to convert that interest into sales. Note that many email programs block images by default, so the results may be artificially low.