An email open rate is an important, albeit unreliable metric in email marketing. Let me explain.

First, what is the open rate? It is just how it sounds, or at least it should be exactly how it sounds. An email open rate can help determine the percentage of emails that were opened in a given email campaign.

The number of emails that were sent and how many bounced factor into the equation for this metric.

email open rate tracking charts

Email Open Rates Can Gauge The Effectiveness Of An Email Campaign To Some Degree

If you are sending emails to a similar audience regularly you can perform certain A/B or split tests. For example, you may want to measure the effectiveness of a campign during a specific time of day, or day of the week.

Clicks and conversion are important metrics but the open rate can help determine if there is an improvement during a day parting split test. Headlines also effect the open rate so looking at open rates can also play into headline tests.

In general the open rate will not be spot on but you can look at fluctuations to determine if your campaign is working, and whether your recent changes impacted the number of times the email was open (and presumably read).

The First Thing That Has To Be Worked On Is Deliverability, Then Open Rates

It is very important that emails make it to the subscribers inbox to begin with. There are many factors that lead to an email not being delivered, which include: whether the sending email address is in the subscribers address book, whether the domain used in the sending email address is considered spammy, whether there are spammy words within the email, whether there is a text version of the email that accompanies the HTML email, and so on.

But once delivered safely, more opens should lead to more clicks, which should lead to more conversions, at least in a perfect world.

The cycle can be looked at as follows (in general):

Get them on the list >> Deliver the email >> Get them to open (and hopefully read) the email >> Get them to click the link >> Get them to buy stuff

As you can see, “opening” the email is just part of the process, but of course an important one. Anything before (and including) conversion is of course an important part of the email marketing process.

Opens Aren’t Always Recorded, Or They Are Recorded In Error

The way open rates generally work is there is an image, usually a 1 pixel transparent image, that exists within an HTML email. Ideally, when a person opens an email, the image will be downloaded to the browser’s cache (a temp location on the subscriber’s computer). The image will contain tracking information in a query string that will fire some code that will update the stats for the email being sent.

A lot of times though, images are turned off in an email unless a subscriber explicitly says to “turn on images.” Other times, if the sender’s email is in the subscriber’s address book images will be turned on. But without that image firing, an “open” will likely not be regiestered.

Sometimes, when an email client has a preview pane, it may appear as though the email had been opened when the subscriber cycles through their emails, when in fact it could have been skipped over. And other times, subscribers opt for text only emails rather than HTML emails, therefore the tracking pixel will not be downloaded.

As you can imagine, the above scenarios will affect the email open rate statistics.

Sometimes An Open Can Be Registered From A Click

Email tracking software, even though the “open” metric is out of their control, can track clicks. That is fully in their control as the URL can not be visited without a click (or copy and paste), at which time the click is registered and the browser is redirected to the web page (or file).

Some marketers turn off click tracking but this could register the “open” when there is no other way. Because clearly if a person clicked a link in the email, the email had to have been opened even though the transparent tracking image may not have fired. Not all email service providers, or email tracking software will up the “open” count when a “click” had occurred, further skewing the results. This could lead to more clicks than opens which in general should not happen.

Leave It To The Email Service Provider To Track Statistics

Some people like to run their own email server and that is fine. Those same people probably have someone on staff to code the tracking scripts and have the ability to insert a 1 pixel transparent tracking image into outgoing emails. Others will rely on 3rd party email marketing companies such as AWeber, ConstantContact, MailChimp, and the like.

Third party newsletter companys will handle open tracking on your behalf. In the same way they tend to keep people in accordance with the CAN-SPAM laws, they generally keep very good statistics.

Some will increase the open rate when they see a click, others will not. Some will count an open more than once from the same subscriber, while others will separate out unique opens. Some will even show you the full behaviour of a particular subscriber which is very valuable information to have. For example, you could know whether the person forwarded the email, shared the archived version, Tweeted or Facebooked the archived version, and so on.

Quick Tips To Increase Open Rates

Coming from a London cyclist who sees open rates as high as 60% to 70%, here are a few tips to keep the rates going up (or at least not going down):

  • Deliver emails at the same time
  • Use the headline, and first line (secondary headline) effectively. i.e. Make certain the first line is not: “Click here if you cannot see this email correctly”
  • Deliver content in emails that cannot be seen elsewhere
  • Tell people what to expect in the next email
  • Take polls to understand your readers and deliver to them exactly what they are looking for (on the blog and in the emails)

Be sure to split test any of the above, one at a time, and look for fluctuation in the stats.

In Conclusion

While open rates can help determine which test, a or b, was effective during a split test, or how good a headline was, it is a metric that should not be taken literally. As shown above it is rarely, if ever accurate.

Take the open rate metric for email marketing campaigns with a grain of salt, but look at them for fluctuations none the less.