33 years of Email what engagement works

Do you know that 33 years ago email was invented and it has taken over the way we communicate today, SendGrid has revealed the results of a study on global email engagement.

SendGrid collected data over two 10-day periods in 2014 and 2015 respectively, with a data set spanning more than 10 billion emails sent.

What SendGrid found from the data include:

  • Apple-manufactured devices retain the crown as the most used platform to access emails. Nearly half of email opens in the US (45%) tracked by SendGrid have been accessed on Mac desktops, Macbooks, iPhones and iPads.
  • Windows-based devices are the second fastest growing segment for email opens globally. On average, emails opened per day on Windows devices in the last year, accounted for a 3.39% increase over the prior year.
  • Android and Linux based devices are the two fastest growing segment for email opens in the US, growing 71.4% in the last year.
  • Canada is the largest region for email readership, representing 7.9% of email opens in the last year. Australia is third in email readership, with 7.0% of email opens in the last year.

SendGrid analyzed 5 million unique subject headers in nearly 18 million emails. This is the fact SendGrid found:

  1. Shorten Subject Headers: While 7 words is the most common subject line word length (14.0% of subject lines), 3 word subject lines (1.6% of subject lines) have the highest engagement rates (21.2%, compared to 17.2% overall and 15.8% for 7 word subject lines).
    • Measuring engagement rates by number of character lines tells a similar story: longer subject lines have lower engagement rates. Past 15 characters, each extra character is correlated with a 0.03% absolute decrease in engagement rate (or about 1% per 33 characters).
  2. Choose Your Buzzwords Carefully: Recipients prefer certain words over others.  Subject lines referring to “yesterday” and“tomorrow” have higher engagement rates (20.5% and 22.3%, respectively)  than “today” (11.8%).
    • Subject lines with “soon” have higher engagement rates (21.9%) versus subject lines referring to now  “now”
    • Email subject lines that use the word “free” have significantly lower engagement rates (13.1% versus 17.2% for “free”-free subject lines).
  3. Eliminate Links and Hashtags: Subject lines that contain URLs do poorly, with average engagement rates of 9.9% (compared to 17.2% for subject lines that do not contain a URL). Subject lines with URLs in them are rare (fewer than 0.4% of emails).
    • Subject lines that contain #hashtags do poorly, with average engagement rates of 10.5% for subject lines with a single hashtag (compared to 17.2% for subject lines that do not contain a #hashtag). Thankfully, emails with hashtags in them are rare (fewer than 0.2% of emails).

Full press release can be found here.