How Long Should an Email Subject Line Be?
To find out, we analyzed 1,000 subject lines.
By Liz Willits May 7, 2019
Your email subject line matters. 47% of people open emails based on the subject line alone, according to research done by Business2Community.
Because of this, marketers ask us about email subject lines often. And one of the most common questions we hear is this: What’s the best length for a subject line?
To find out, AWeber’s team of email experts analyzed 1,000 subject lines from 100 of today’s top marketers. Here’s what we discovered.
What is the average length of a subject line?
We found that, on average, these experts’ email subject lines included 43.85 characters.
For perspective, the below subject line from the daily email newsletter theSkimm is 43 characters in length.
Subject line: Daily Skimm: I’ve got the world on a string
How to write a stand-out subject line
71.1% of the 1,000 subject lines we analyzed were between 21 and 60 characters. To stand out from everyone else, we recommend you don’t keep your subject lines within those bounds. Instead, try the 2 methods below:
1. Keep your subject lines really short.
46% of emails are opened on mobile devices, according to research conducted by email testing service Litmus.
Most email clients, like Gmail and Yahoo!, stop displaying an email subject line on mobile devices once it reaches between 33 and 43 characters. The exact number varies from one email client to another.
To optimize your subject lines for mobile readers, use subject lines with less than 30 characters. This way, your subject line won’t get cut off in the inbox.
Or, you might want to experiment with even shorter subject lines. Brian Dean, founder of SEO company Backlinko and one of the 100 top marketers whose emails we analyzed, used to send emails with longer subject lines. These subject lines told his subscribers exactly what they’d find inside the message. The problem with that? “It gave people no reason to actually open my email,” he said.
Now, he sends subject lines with an average of 15.1 characters. “After lots of testing, I’ve found that short subject lines get much higher open rates,” Dean said. He contributes this to 2 factors:
- Short subject lines reach the inbox more frequently.
- Short subject lines are more mysterious.
Here are a few of Dean’s short email subject lines. All are under 15 characters long:
Subject line: New Technique
Subject line: Email Outreach
Subject line: Blog Posts
2. Use really long subject lines.
You can also stand out in the inbox with really long subject lines, since only 18% of people include more than 60 characters in their subject lines.
This email subject line from social media platform Sendible stands out in the inbox because of it’s unusual length of 111 characters.
Subject line: “Be Your Freaking Self”: 11 Experts Have Their Say on the Future of Social at Social Media Marketing World 2019
Copywriting expert and Copyhackers Founder Joanna Wiebe recommends you either use very short subject lines or very long ones. These subject lines will stand out from everyone else who uses subject lines around 50 characters in length.
“Subject line length absolutely matters,” Wiebe said. “We prefer one- or two-word subject lines above all else. To mix things up, we also add realllllllly long ones.”
Here is one of Wiebe’s short subject lines:
Subject line: Got wins?
And here is one of her longer subject lines:
Subject line: My template for your “messaging recommendations report” <– live in today’s Tutorial Tuesday
Test your subject lines out.
Every audience is different. Try short and long subject lines with your subscribers to see what works best for your unique audience.
Ready to start using this data to send better emails? Sign up for your free 30-day trial of AWeber today.
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About the data from this research
We analyzed 1,000 marketing emails from 100 successful businesses and entrepreneurs. While we didn’t randomly select these businesses, we chose experts across multiple industries and from numerous countries.