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The Preview Text Hack You May Want to Use in Every Email [Updated]


Did you know there is a preview text hack you can use to make the most of this valuable email real estate? Because your email’s preview text in the inbox shows at least as many characters as your subject line—(and in some cases, much more) it can be difficult to optimize. That’s because email clients always pull in enough characters to fill all available preview text space (up to 5 lines). That means you’re left with two choices:

  1. Go long and have it cut off, which can create embarrassing truncation.
  2. Go short and have URLs and other “non-optimized” content from your emails pulled in to fill the space.

Enter, the little-known third choice…

The preview text hack

Did you know you can create white space after your desired preview text so that email clients don’t pull other distracting text or characters into the envelope content?

In most cases, all you need to do is add a chain of zero-width non-joiners (‌͏ and ‌) and non-breaking spaces ( ) after the preview text you want displayed. The repetition of ͏‌  then fills any remaining preview text space.

There are caveats, though. As of March 2023, it seems that in some cases, this preview hack may not work. Email clients are always changing (on average, every 1.2 days) and it might not work everywhere.

Even if the preview text hack doesn’t work in all places, that’s not a reason to stop using it. It just means the preview text hack should be considered as a progressive enhancement—a way to give subscribers a better experience if they have an email client that supports it—instead of it being a hack that works everywhere.

Whether it’s due to your ESP or an email client that is having a bad day, there may be times you’ll need to play around with the above preview hack to make sure it works.

Here are some ways to do it:

  • Mark Robbins has a variation in his library of Good Email Code where he alternates the HTML entity ͏ and a space as the preview hack:

    ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏
  • We’ve also seen it done by adding spaces to the original hack:
    ͏ ‌   ͏ ‌   ͏ ‌  
  • June 2023 update: to get the most coverage, Mark Robbins suggests adding   and ­ as these HTML entities add space that are still supported in Yahoo and iOS 16.4.

The bottom line: If the hack shows up in your preview text, play around with different variations to see if you can find one that works.

You can see where to insert the code in this example:

Insert hidden preheader text here.

 ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌
<div style="display: none; max-height: 0px; overflow: hidden;">
Insert hidden preheader text here.
<!-- Insert &#847;&zwnj;&nbsp; hack after hidden preview text -->
<div style="display: none; max-height: 0px; overflow: hidden;">
&#847; &zwnj; &nbsp; &#8199; &shy; &#847; &zwnj; &nbsp; &#8199; &shy; &#847; &zwnj; &nbsp; &#8199; &shy; &#847; &zwnj; &nbsp; &#8199; &shy; &#847; &zwnj; &nbsp; &#8199; &shy; &#847; &zwnj; &nbsp; &#8199; &shy; &#847; &zwnj; &nbsp; &#8199; &shy; &#847; &zwnj; &nbsp; &#8199; &shy;


The backstory (and new story) on the preview text hack

The preview text hack used to only consist of a string of &zwnj;&nbsp;, but the email community (and our recent testing) discovered that that preview text hack doesn’t work with Yahoo Mail. Our email marketing specialist, Carin Slater, recommends using all 5 HTML entities  so “then you’re covering all your bases, and offering the best experience for your subscribers when it’s supported”.

But, since email clients make updates pretty often that can break your emails, it’s important to make sure you always test your preview text (and the rest of your emails)!

We’d also like to give a special shout out to Litmus Community member Ryan Field who mentioned this technique in 2016—and called it a “super old” preview text hack. While that may be true, hardly anyone was using it.

Nearly 35% of respondents from our LinkedIn poll still don’t know about it.

Preview Text Hack

Hopefully, we’ll continue to see the use of the preview text hack climb.

How brands are using this hack

Looking for inspiration on how to use this trick?

We’ve been using this hack in our Litmus emails from the monthly newsletter and Litmus Weekly, to product announcements and event invites. Here’s how some of them look like in Gmail:


Check out some more examples of other brands successfully using this hack to optimize their preview text:


Does it impact email deliverability?

While there are concerns from the community and email marketers regarding email deliverability and use of this hack, we haven’t experienced any issues. We’ve been using the preview text hack across different campaigns for many years now without ever seeing a negative impact on deliverability. If anything, it might help deliverability since this can create a positive subscriber experience, which leads to engagement. (The inbox providers love that!).

But, as with most things in email, if you do want to use this hack but are concerned about how it could impact your deliverability, use email A/B testing to see if your subscribers respond positively, and ensure your deliverability rates remain stable.

Take control of your preview text

The popularity of this hack is increasing, but there are still many brands who have yet to use it. So give it a try and see how you like it. You’d never leave your subject line to chance, so take control of your preview text as well.

Insert hidden preheader text here.

 ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌
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Originally published on July 11, 2018, by Chad S. White. Last updated June 23, 2023.