This is the best way to start and end your emails, according to experts who reviewed 350,000

The smiley faces in your emails are making you look bad
The smiley faces in your emails are making you look bad

A lot of people use the wrong tone in their emails, a recent analysis of nearly 350,000 messages from productivity software firm Boomerang finds. And it can hurt you: People write back significantly more often when you get the tone of your email right.

Boomerang data scientist Brendan Greenley looked at messages from mailing list archives of over 20 online communities from different industries, extracted the opening and closing lines of each email and correlated them to the response rate each email received. His main takeaway? Be friendly.

"Perhaps we should move past the era of formal salutations," Greenley notes in a blog post. "Messages that struck a more informal, conversational tone from the start got more responses."

Here's what Boomerang found are the most effective email openings and closings in terms of getting someone to write you back.

The best way to start an email

"Hey" and "hello" are both winners, generating a response rate more than 15 percent higher than a formal "dear."

Overall, Greenley found that "while omitting a salutation on follow-up replies seems to be increasingly common, it looks like you are best off including an opening, at least in your initial email."

The best way to end an email

Greenley found that "thankful closings" in emails received the most responses, and especially the cheery, optimistic phrase, "Thanks in advance."

By contrast, Greenley found that "best" is the worst way to sign off.

Given that people tend to match the tone of whoever they are emailing with, Greenley notes that the most important thing to do is "keep your audience in mind when you're starting to write a new message."

Since tone can also be lost over text onscreen, here are five common mistakes to watch for when sending your next email.

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