Diving Into The Data

When I was the head of marketing at Boomerang the tool started out as an extension for Gmail and now has evolved into a multi-platform system. Boomerang has plugins available for Outlook and Office 365 as well as apps for both iPhone and Android.

As a data nerd myself, I love that Boomerang’s products are developed based on academic research and data. I wanted to share some insights we learned on how to improve open rates, increase conversions, and get more people to say “yes” to your email.

There’s a lot of advice that sounds good but is actually contradictory to what the data says. That only made me want to dive into the data more and figure out what was going on.

I want to tell you what I’ve found.

The first area I want to discuss is subject lines. They are the first touchpoint where someone decides whether or not to open and read an email.

If they’re not going to open your email it doesn’t matter what the content inside is. We analyzed over 5 million emails and looked at the commonalities among subject lines that got more opens against the ones with fewer opens.

Overall, shorter subject lines did better. Subject lines with three or four words received the most responses.  
When you’re crafting subject lines you want to fit what’s relevant into them but with each word, you add your response rate might be taking a hit. Efficient subject lines are particularly important when you’re optimizing for mobile.  
The next question is “What should you include in your subject line?” Words like “Opportunity, Demo, and Connect” tend to get you more opens than “Join, Assistant, Confirm, and Press.”

We’ve used this information to improve our own marketing emails. When I was at Boomerang, we offered a bi-monthly webinar for our users.

After going through our data we realize that if we called the webinar a free demo instead it boosted our open rates by 7%.

Little shifts like that can have a big effect on getting past Gmail’s internal filtering system and keep you in the main inbox tab instead of promotions or the social tab.  

Action Steps

  1. Write 3 to 4 word subject lines, if your subject lines are longer try rewriting using the 3 to 4 most relevant words.
  2. Use words like “Opportunity, Demo, and Connect,” rather than “Join, Assistant, Confirm, and Press.”
  3. Look through the emails in your sequence and rewrite your subject lines to fit this criteria.
  4. Split test word choices and keep making improvements according to your own data.


Result You Will Achieve

Better subject lines that will increase your open rates and list retention.

Mentor: Chris Cichon

Growth Leader at Grove Collaborative, Former Marketing at Boomerang. Chris has educated thousands of people on email productiveness and been a key part of building the world’s leading email productivity software with over 3 million users.

This article is based on an EHQ interview with the mentor.