In today’s multi-media world filled with time-pressed customers, the challenge of getting and keeping their attention has never been greater. Even when customers opt-in to receive e-mail communication, there is no guarantee that they will open it. That is why open rates are such a key metric for e-mail marketers.
In simple terms, open rate refers to the number of people who open a particular e-mail. The most basic way of calculating it is: e-mails opened divided by e-mails delivered (in other words, minus bounces). The open rate can be used to track the success of a campaign. They also serve more pragmatic purposes, such as keeping e-mail lists clean. Companies do not want to waste time and effort trying to contact customers who are either unreachable (having changed e-mail address for example) or uninterested.
In order to determine when an e-mail is opened, the sender typically uses a tracking ID embedded in an image. E-mail images have to be downloaded from an external server, which means that as soon as the recipient connects to the server to download the image, the unique ID can be recorded and the e-mail considered to be opened. While this system has worked very well for a long time, it is far from foolproof. Some users opt to receive plain-text e-mails (i.e. those without images) or simply turn off the option to download images from external sources (or leave it turned off by default in their browser). Whereas previously this may have been done for reasons of security, today’s internet users are increasingly likely to be using mobile devices and to be conscious of their data usage. Additionally, Google has just introduced image caching for Gmail and it remains to be seen how this will impact legitimate commercial e-mail. If Google relays the individual tracking ID with each download, senders will still have at least some visibility over who is opening what, but if they manage to implement a caching system where they only download the image once and send it to multiple users, it will be effectively impossible to track individual openings using this method. Commercial mailers may move to adopting alternative strategies to measure open rate, such as having a user click on a link to access the content. This approach may, however, be less than ideal for users of mobile devices.
Even when the open rate can be measured successfully, it still needs to be treated with a note of caution. In point of fact it is something of a misnomer in that it only identifies when a user has downloaded images for an e-mail rather than whether they have actually given it any further attention. It is therefore best looked upon as a useful guideline rather than as an exact science, and really the best way to get a handle on a typical open rate is to track it over time and be alert to any variation. However, the basic rule of thumb is that the more targeted the list and the more engaged the readership, the greater the open rate. At its most basic level, this means keeping e-mail lists clean and removing addresses where there has been no action for a defined period. Ideally, it means generating clearly focused lists (e.g. by special interest or local area) and keeping readers engaged from issue to issue (e.g. by including interactive elements such as competitions).
Step number one in getting people to open subject lines is to get them to the right addresses. There is no point in continually sending e-mails to addresses where there is never any sign of a reaction. Clean your mailing list and focus on customers where you at least have a chance of getting a response. Step number two is to get your mails past spam filters. This means being careful with subject lines. Avoid words which suggest that the content contains sales pitch and if at all possible avoid symbols and exclamation marks. Spam filters tend to look upon these with suspicion having been developed to filter out “vi@gra!!!” and the like. By a happy coincidence, this will also often help with step three, which is getting the human recipient to pay attention to the subject line.
The subject line should inform and engage rather than attempt to sell. Think of how you react to a salesperson pushing themselves upon you when you are browsing a shop rather than actively looking for assistance. That’s how pushy e-mail subjects look to readers. The old rule about capital letters looking like SHOUTING holds as true for subject lines as it does everywhere else. They are also looked on unfavourably by spam filters, which is another good reason to avoid them. Once you’ve got your reader past the subject, the opening lines of the e-mail must engage the reader’s attention. Whatever the most important point of your e-mail is, get it in quickly. While this isn’t technically measured in open rate, it is, essentially the object of the exercise. Be prepared to experiment. If your open rate isn’t how you’d like it, try sending your mails on different days. Try splitting longer weekly e-mails into shorter daily ones. Try using Twitter to advertise what the current e-mails key points are. Continual innovation is the way to e-mail success.