Having trouble getting replies to your emails? Apparently, one of the best ways to get a reply is to write as if you're 9 years old.

That's according to the makers of the Boomerang mail plug-in, who found that writing at a third-grade reading level seems to be the right level of complexity for the average message, after mining their user data for information on what kind of writing actually gets replies.

Before we all panic about the dumbing down of society, however, it's worth taking an extra moment to think about why you would want to write in a way that a 9-year-old can grasp. Email gets a bad rap these days — in fact, its death has been declared quite a few times — and is often criticized for being inefficient and clunky. Sure enough, looking at more email-writing tips from Boomerang, the key to making your messages better is to keep a focus on simplicity.

To get replies, the company suggests using shorter, simpler sentences — hence the third-grade reading level. Writing this way generally gets a response rate of 53 percent, as opposed to 45 percent for messages written at a high school reading level. Writing too simply also drops your chances of a reply — messages written at a kindergarten reading level get replies only 46 percent of the time. But the worst response rate was for those writing at a college reading level, at 39 percent. Apparently — as many third graders will tell you — no one likes a smarty-pants.

The company also found that being a little more expressive is a good way to get responses. Having an opinion and adding a little emotional tone (positive or negative) gets you better results than being completely neutral.

There's also a sweet spot for how much you should say — get too wordy and people aren't likely to write you back. If you're too terse, you also get a fairly low response rate.

Here's a full list of the tips from the makers of Boomerang:

  1. Use shorter sentences with simpler words. A 3rd grade reading level works best.
  2. Include 1-3 questions in your email.
  3. Make sure you include a subject line! Aim for 3-4 words.
  4. Use a slightly positive or slightly negative tone. Both outperform a completely neutral tone.
  5. Take a stand! Opinionated messages see higher response rates than objective ones.
  6. Write enough, but not too much. Try to keep messages between 50-125 words.