Open Rates and Click Tracking

In the Spring Cleaning article two weeks ago, I mentioned open and click tracking. That allows you to see how many of your list readers open your messages, and/or click the link(s) in a mailing. Here, for instance, are the stats from the most-recent mailing in my AWeber account (the methods are similar at other ESPs):

At send time on Monday morning, that list (a new-posting announcement list for my joke site) had 1,813 subscribers. As of when I grabbed the above screen shot (as I was writing this Tuesday evening), 56.4 percent (1,021 readers) had opened the message, and 46 percent (of the total, or 832 readers) clicked on a link in that message. (“Bounced” shows the messages which were undeliverable — bad address, mailbox full, or other causes — and “Complaints” tracks how many readers clicked the “This is Spam” button at a mail provider which provides a “feedback loop” to the sender — in this case, AWeber. At AWeber, at least, when they get a spam complaint, the reader is automatically unsubscribed.)

But all this begs the question: How do they know how many subscribers opened the message, and clicked a link?

Excellent question. Most ESPs use two methods for such tracking: a “tracking pixel” in the message, and “tracking links” for any links you include in the message. Let’s take those one at a time.

Tracking Pixels

The tracking pixel is a one-pixel image that’s embedded in each email sent to your list members. When the reader’s email program or service (Outlook or Gmail, for examples) allows images to be included in the message, and the message is opened, that image is displayed. It’s probably just a white (or even transparent) pixel, so the reader doesn’t even notice it, but it’s loaded from AWeber itself, so AWeber knows that pixel was called for. How does that help? Each mailing list has a list number (let’s call your list #ABC1234). Every subscriber on that list has a subscriber number (let’s call Joe Subscriber on that list #XYZ9876). And finally, the message you sent Tuesday has a message number (let’s call that 2468MSG). The pixel’s URL, then, might be — and if that pixel is called for, then AWeber “knows” that subscriber XYZ9876 on list ABC1234 opened message 2468MSG, and increments your stat for that message by one open. (The list/message/user information isn’t quite that plainly broken out and displayed, but you get the idea.)

Can you see how that might be helpful? It’s nice to know that your readers are paying attention …or not.

But there were some “ifs” in there: what “if” the user (or their software) doesn’t allow embedded email images? Or it does, but what “if” the user has images turned off? Then simply, those opens won’t be counted. Thus, the “open rate” shown here (56.4 percent) is a worst case scenario. We only know that at least that many readers opened the message. The “open rate” varies considerably in email publishing; 30-40 percent is considered quite good, in general. And, again, the open rate number you see will be a worst-case minimum: some just aren’t counted. (What if a particular reader opens the email 2 times, or 20 times? Those extras might be counted separately, but the open rate itself doesn’t increment since that reader was already counted.)

Tracking Links

OK, so it’s nice to know readers are opening your messages, but you probably have some sort of “Call to Action” in your message: click for a blog post, click to buy something, click to see a video you recommend, click to …whatever. In each case, a click is involved.

When AWeber (and most other ESPs) track clicks for you, they can do it two different ways: first, by completely changing the link, so that your link to becomes something like (see the similarity to the tracking pixel above?) When a reader clicks that, AWeber counts the click, and quickly redirects the reader to the URL you intended. It happens so fast they’re unlikely to see the detour.

There’s a drawback to that default URL change, though: if your reader pays attention to such things (and more and more, smart subscribers do), your readers are expecting your URL, and may not even know what “aweber” is. They may be wary about clicking a link if it’s not to someplace they expect to go. So AWeber, at least, has an alternative method: you can put an AWeber-provided script on your web site so that you can use your own domain, and the tracking links will look something like this: — the same information, but attached to the end of your URL, with no intermediate redirect on AWeber’s servers. Yet the script on your site sees the click come in and reports the click back to AWeber so that your stats can be incremented. Readers who pay attention are not likely to be alarmed by the information appended to the end.

And here’s something tricky: you know the readers whose “opens” aren’t counted because for one reason or another, they don’t call for the tracking pixel? Well, if the subscriber clicks a link, and that link click is counted, that’s an “implied open” (else how could they click the link?), and that user is shown to have opened that message. Cool! That helps make the open rate that much more accurate — but it still won’t count those who don’t call for the pixel and don’t click any links, even if they read every word of your email. There just aren’t any more accurate ways to determine whether your reader opened a specific email than this.

The resulting data can be very powerful. You could, for instance, set up a “list segment” at AWeber for “any subscriber who clicked THIS link” and send them all a follow-up message — a message that only goes out to that specific group. And the possibilities implied by that should get your juices flowing!

Even if you’re not doing something that sophisticated, though, having all this tracking going on allows you to do your “Spring Cleaning” to clear uninterested subscribers off your list, saving you money and increasing your sender reputation, as discussed in the Spring Cleaning article.

Another Important Consideration to Consider

So here’s a helpful “advanced user” tidbit. There are right and wrong ways to format links in emails, especially with link tracking in mind:

Wrong Way: <a href=””></a> — a link that is “anchored” on text showing the link.

Why: When the actual link is changed by your ESP so it can be tracked, it then becomes something like:

<a href=”″></a>

Why is that bad? First, since that’s a very common spammer trick, your message is very likely to end up in the spam bucket. Even if it’s not dumped into spam, when a reader tries to click the link, many email programs will warn them that the actual link doesn’t match the displayed link …because that’s a common spammer trick. Either way, you’re not likely to get many clicks — and that’s why you sent the email in the first place, right? To get those clicks?

Right Way: <a href=””>my video</a>

(or “the order page” or whatever), since even if that is rewritten by your ESP to something like

<a href=”″>my video</a>

there won’t be a mismatched link warning thrown up to worry your reader.

This just scratches the surface about what you can do with such tracking statistics. The idea here is to show you how it works so that later, you can do things (such as spring cleaning). I’ll cover more about other advanced techniques this tracking enables in a later article.