Last quarter, newsletter giant The Hustle ran a test that earned 43,876 additional clicks in their emails.
Not 44,000 total. 44,000 more.
If you¡¯re like me, you¡¯d do terrible things for that kind of engagement.
So I banged on their managing editor¡¯s door and demanded to know his secrets.
Thankfully, the process is simple and repeatable ¡ª no terrible things required. So put down that crowbar, because I¡¯m going to share a process that you can start today.
The How-To That They Do
Ben Berkley, the managing editor of The Hustle, perpetually sports an impish grin. Which is fitting, because behind that grin is a deceptively simple method ¡ª with some twists coming up.
Here¡¯s how it works:
Every weekday morning, Ben cooks up two separate subject lines for each newsletter. At 5:30 am ET, each subject line is sent to only 30% of The Hustle¡¯s audience.
After an hour, the variant with the most engagement is automatically sent to the remaining 40% of recipients.
¡°That¡¯s it?¡± you¡¯re thinking. ¡°It¡¯s just a stinkin¡¯ A/B test?!¡±
Not so fast. I promised you twists:
- The variations are sent to four predefined subscriber segments.
- The winner is based on the click-through rate (CTR) ¡ª not the open rate.
- Ben¡¯s secret sauce: The WTF factor.
Let¡¯s dig in.
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Twist 1: Segmenting Readers
The Hustle splits the original two test emails among four segments.
To help me understand this, Ben refers me to Kaylee Jenzen, The Hustle¡¯s resident MarTech wizard.
(¡°If the Nobel Foundation ever adds a prize for newslettering, I'm nominating Kaylee so fast,¡± he says.)
¡°The Hustle uses to segment contacts with values ranging from 1 through 4,¡± Jenzen explains. ¡°Email 1 is targeted at segments 1 and 2, while Email 2 is directed towards segments 3 and 4.¡±
In other words: One email, two variations, four sends. The reason?
¡°By distributing email sends over time, The Hustle avoids triggering spam filters and ensures more consistent delivery rates,¡± Kaylee says.
The takeaway: High send volumes are a signal that email service providers use to identify spammers. By reducing your recipient list and increasing send times, you make your emails safer in the eyes of email servers.
Twist 2: Targeting CTR, Not Open Rate
If you¡¯ve tried A/B testing your subject lines before, I¡¯ll bet you based the test on open rate, right?
That¡¯s what nearly every tutorial will tell you, and it¡¯s not a bad choice. But it¡¯s not the only choice.
While open rate measures the number of readers who access the email, it can¡¯t separate out those readers who delete it immediately. Click-through rate, on the other hand, measures the number of readers who actually engage with the email.
¡°By emphasizing CTR, The Hustle aims to not only capture the reader's attention, but it also encourages them to take action and interact further with the content,¡± Jenzen says. ¡°This approach reflects a strategic effort to drive meaningful engagement beyond just opens.¡±
See, The Hustle¡¯s open rate is already above industry average, so tweaking the subject line only results in around a 1% difference in that metric. (#HumbleBrag?) So instead, its team makes the strategic choice to focus that time and effort on cultivating even deeper engagement.
The takeaway: Open rate might be the metric you want to focus on. But think about your ultimate goal. Optimize to achieve that, not what a YouTube tutorial told you to do.
Twist 3: The WTF Factor
¡°When people are looking through their inboxes, they¡¯re often just looking to clear all the new stuff out,¡± Ben says. ¡°And they get in a rhythm.¡±
That rhythm is the sound of your email being deleted.
¡°So the goal is to gently jostle someone out of their rhythm,¡± he says.
That¡¯s where Ben¡¯s secret sauce comes in.
¡°To do that, you need a little ¡®WTF?¡¯ factor sprinkled in.¡±
As the former executive editor of The Onion, Ben¡¯s no stranger to the WTF factor. But that doesn¡®t mean that he¡¯s trying to recreate Onion headlines for The Hustle.
¡°I never go for shock value or try too hard to throw people off,¡± he cautions. ¡°But you ultimately want them to see something unexpected and give them a quick pause. You just want them to glitch for a split second.¡±
Some of my favorite examples:
- ? Believe in yourself, but not like this
- ? Buried under cement in a landfill
- ? Breaking out of toothpaste jail
The takeaway: Your subject line should be surprising enough to shake them out of autopilot and spare a few minutes for your email.
But what does that actually mean?
How to Write Subject Lines Like The Hustle
Ben shares with me what he calls his ¡°Subject Line Manifesto.¡± These are actual guiding principles for The Hustle¡¯s editorial voice.
1. Be unexpected.
You¡¯re not likely to jostle someone out of their rhythm with a subject line that confirms something they already know.
¡°Having worked in comedy, I know the power of subverting expectations,¡± Ben says. ¡°It¡¯s at the core of getting laughs and creating something memorable.¡±
¡°Excluding all of the other actual unforgivable crimes, there¡¯s just one unforgivable crime at The Hustle,¡± he adds. ¡°Being boring.¡±
That »å´Ç±ð²õ²Ô¡¯³Ù mean you have to try to be funny. In fact, that may be inappropriate for your brand. You can subvert expectations with new data, surprising ideas, or a thoughtful question.
What part of your email is adding something new to the conversation? That¡¯s your subject line.
And speaking of which¡
2. Strong subject lines come from strong stories.
¡°The subject line has to match the newsletter¡¯s overall vibe, and also the specific content within each day,¡± Ben explains. ¡°So really, the work of writing a strong subject line starts with the work of writing strong stories.¡±
So if your email »å´Ç±ð²õ²Ô¡¯³Ù add anything new to the conversation, maybe pause the subject lines for now and revisit your content strategy.
3. Don¡¯t go for cheap laughs.
If you do decide to use humor, don¡¯t use the same pun that 10 of your competitors also used. Chances are, an example just popped into your head. Skip that one.
¡°Low-hanging fruit in comedy is low for a reason; it¡¯s there because it¡¯s what people expect,¡± Ben adds. ¡°If you give it to them, maybe you get light laughs, or a pity laugh or two, but you¡¯re probably not getting a belly laugh because they weren¡¯t surprised. Valuable content comes from jolts.¡±
And while we¡¯re on the subject¡
4. Never stoop to clickbait.
¡°It¡¯s so easy to have a subject line feel like clickbait, and that¡¯s the last feeling we want our audience to have,¡± Ben warns. ¡°In this hypercompetitive attention economy, if you sour that relationship, you¡¯re never getting it back.¡±
5. Keep it brief.
The Hustle sees a noticeable lift in performance from subject lines that are only 11-15 characters long.
Their shortest subject lines enjoy an engagement rate almost 75% higher than emails with the longest.
¡°As I approach subject lines, I always remind myself: Those words are there to whet the palate, not overwhelm it,¡± Ben says. ¡°You need to give them just enough context to pique their interest, but not so much that they feel like they already have the whole story.¡±
Now that you¡¯re a subject line expert, let¡¯s talk process.
How to Do the Test at Home
Sending multiple emails every day sounds like a ton of work, and it would be if you did it manually. Thankfully, most email marketing tools have some kind of automated A/B testing feature.
The Hustle happens to use , so we¡¯ll show you how to do it within 51³Ô¹Ï, but the process should be nearly the same no matter what tool you use.
1. Create your email as usual.In 51³Ô¹Ï, as with most tools, this will automatically be version A of the A/B test. (So name it accordingly, and give it your first subject-line variation.)
2. Click on ¡°Create A/B test¡± in the top left corner.
3. Enter a name for version B, then click ¡°OK.¡±
Don¡¯t overthink this. Naming conventions are one place where it¡¯s safe to let your boring side show.
Even Ben forgives it in this screenshot below.
Remember that a best practice for A/B testing is to only change one element per test. Otherwise, you¡¯ll risk skewing the results.
5. Under the version dropdown menu, click ¡°Manage test.¡±The Hustle uses 30% of their recipients for each variation, with 40% reserved for the winner. But with over two million subscribers (#HumbleBrag confirmed), it can spare a few readers to get more accurate results.
If you have a smaller send volume, you may wish to stick with 20-25% for each test version. While your test will be based on a smaller sample size, the proven winner will be seen by more recipients.
7. Set the winning metric to ¡°Click Through Rate.¡±To replicate The Hustle¡¯s method, you¡¯ll want to choose CTR. That said, consider the goals of your campaign.
The tool will also allow you to choose ¡°open rate¡± or ¡°click rate.¡±
8. Set ¡°Test duration¡± to 1 hour.You¡¯ll see a warning to set a duration of ¡°at least 4 hours¡± in order to help reach conclusive results.
That¡¯s good advice for most marketing emails, but it can be a problem for newsletters. 51³Ô¹Ï research shows that the best send times are between 9am to noon Eastern time.
You can see why a four-hour test might complicate that. But what you¡¯ll lose in statistical significance, you¡¯ll make up for in eyeballs.
9. Click ¡°Save changes.¡±Get Your Hustle On
To assuage our legal department and prevent you from banging on my door: I can¡¯t promise you 43,876 additional clicks.
But by following a data-driven approach, you¡¯re almost guaranteed to see improvement. Pair that with Ben¡¯s advice, and you¡¯ll be jostling your readers out of their rhythm regularly.
At the very least, you¡¯ll never be boring.

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