The Perfect Email Is Short, Simple, And Not Too Emotional

Please try to write better emails, for all of us.

The Perfect Email Is Short, Simple, And Not Too Emotional

If you send someone a text, it will probably be read immediately. But if you send an email, it’s just as likely to slip onto the second page of unread messages in the recipient’s inbox. The folks behind Boomerang, the email-processing tool, took a look at their sea of message data and worked out how you can get your message read. It’s instructions on how to write the perfect email.


Last year, Boomerang monitored 40 million emails, giving it a deep and wide data set to mine. So, what’s the secret to writing an email that gets not just read, but moves the reader to respond?

The main trick is to keep it simple. “Our most surprising finding was that the reading grade level of your emails has a dramatic impact on response rates,” says Boomerang’s Alex Moore. “Emails written at a third-grade reading level were optimal.” Short words and short sentences win, getting a 53% response rate. This compares to a similar 46% for kindergarten level, and 45% for high-school level, but most depressing is that emails written at college level get the worst response—just 39%.

You should also keep things positive, but don’t get carried away. Flattery also works, but again, don’t lay it on too thick. And, perhaps counterintuitively, moderately negative subject lines scored about as well as moderately positive ones; both were 10% to 15% better than neutral. Here are some examples, taken from Boomerang, with the rankings of how positive they are:

  1. Hey, I was thinking about you earlier. Do you want to get pizza? 0.0, true neutral.
  2. Hey, I’d definitely like to get together next week. Do you want to get pizza? 0.35 positive sentiment.
  3. Hey, it would be really great to see you and catch up. Do you want to get pizza? Positive 0.55 sentiment.
  4. Hey! It would be absolutely wonderful to see you! Do you want to get pizza? I’m so excited! Over 0.9 positive sentiment.

Of these, number two is the most effective—just a little positive, but not too pushy. For contrast, here’s the perfect negative subject line:

  • I had an awful experience at your store today. The clerk was very rude. Please do something to make it right. Negative 0.35 sentiment.

Interestingly, one great source for Boomerang’s sentiment-analyzing algorithms is movie reviews, “Since they come with a numerical score that can be used as a proxy for how positive the review is likely to be,” says Moore.

Length is also important. Keep it short—125 words is the optimum length—but don’t worry too much if you need to go over that, because response rates don’t really drop until you reach 2,000 words, by which time your recipient is too busy sleeping to hit the reply button.


Boomerang’s analysis also addresses questions and tone (subjective vs. dry), but the overall rule is simple: Keep your emails easy to read and easy to reply to, and don’t scare anybody off by being too enthusiastic (or too negative). If you ever left an important essay-length email from your wonderful mother languish in your inbox without a response while you banged out replies to shorter, easier-to-process messages, then you know this instinctively. If email is going to rule our lives—both at work and in our social circles—the least we can do is try to be better at it.

Related: 2 Useless Phrases You Need To Eliminate From Your Emails

About the author

Previously found writing at, Cult of Mac and Straight No filter.