Optimize Newsletter Subject Lines with Unicode Symbols | DMA

Filter By

Show All

Connect to


Optimize Newsletter Subject Lines with Unicode Symbols


How to leverage Unicode symbols in subject lines


For a long time, Internet users had a limited number of symbols to choose from. As far as ASCII, a character encoding standard (from back of the 1960s), is concerned it contained only 128 characters, 33 of which were non-printable.

During data exchange between different computers and operating systems, non-printable characters led to several difficulties… which haven’t been completely eliminated. The thing is that hardly any language comes with ASCII characters alone. ISO/IEC 8859, a common series of character encodings, also presents limited symbol opportunities. Some alternative characters simply won’t display, especially in email messages. Incorrect settings on the sender or on the recipient part always cause problems. Therefore, it is often recommended to use only ASCII characters only or at least when establishing the from name or when crafting a subject line.

Various problems related to international data exchange led to set out to compose the universal character set in 1980s. The first version of the Unicode standard was published in 1991. This year also saw creation of tools necessary for a working Web – the first HTTP server software, the first Web browser as well as HTML. Unlike previously, Unicode allows for long-term display of all the characters used across the world.

Unicode today

The current Unicode version dates back to 2016 and contains over 128,000 characters. Characters are displayed in all common operating systems. One of the most commonly used encoding is UTF-8, which has become the main storage encoding on most Unix-like operating systems due to its easy replacement for traditional extended ASCII character sets. Other commonly used encoding is UTF-16, which is used for encoding on Windows operating systems. When it exchanges data with different systems, this may lead to wrong display of characters. However, this blog post aims to highlight how to optimize newsletter subject lines with Unicode symbols to your advantage.

There’s more to Unicode than just letters and numbers

Unicode isn’t limited to characters only. Over the years, many other symbols have found their way into the character set. There, you can find anything from smileys and hearts to chess figures and arrows, as well as peace signs and yin and yang characters. Hermann Zapf left a huge typographic legacy, having created ITC Zapf Dingbats, which is one of the more common dingbat typefaces.

In addition to dingbats, the Unicode contains blocks, which display frame elements or geometric shapes. Miscellaneous symbols represent various glyphs, such as snowmen ☃, skulls ☠ and umbrellas ☂.

Such symbols allow for easy communication on the Internet. Most importantly, however, you can use Unicode characters to your advantage. Optimize newsletter subject lines with Unicode symbols.

Pros and cons of Unicode symbols in subject lines

Going for a Unicode symbol will render your subject line more noticeable and interesting. At the same time it might prove to be a disadvantage: some subscribers will be caught off guard and treat it suspiciously due to limited Unicode support in the previous years.

You probably aim to reach a broad audience with newsletters. The thing is that they use different devices, operating systems and email software. A newsletter, which looks great on a Windows computer with the latest Outlook version, might display completely differently on an iPhone. Some users that haven’t configured their email programs properly, or are using out-of-date software won’t be able to see correct Unicode symbols in email them correctly or won’t see them at all. If you want to be sure that your subject line displays, it’s prudent to go for ASCII characters only. However, not everyone should fear incorrect display – it all depends what is your target group.

If an Internet user has subscribed to several newsletters, as well as receive social media notifications into the inbox, deletes spam and, of course, receives news from friends and colleagues, they rarely have the time to go through every single they receive. Full inbox often results in neglected newsletters. Unicode symbols that fit well within the subject line will definitely attract attention.

Do symbols in email subject lines impact the open rate?

So far, there aren’t reliable statistics on Unicode symbols in emails. Therefore, it is difficult to assess whether they have a measurable effect on open rates. According to Experian’s research, subject lines with symbols had a higher unique open rate in 56 percent of brands the company analyzed. Unusual symbols such as airplanes or umbrellas often led to the an increased open rate, whereas popular glyphs only increased the open rate by about two percent.

Important tips for newsletter optimization

If you‘re considering to include Unicode symbols in subject lines, it would be prudent to see what characters are available. Bear in mind that Unicode display might not be correct and that some symbols prove to be difficult on their own.Before you go off sending out a new newsletter to your subscribers, you should test it thoroughly using a newsletter tool.

Unfortunately, you can’t continue to attract attention with the same symbols all over again: the Experian study showed that a glyph won’t cut it if you use it frequently. A neatly placed coffee can make the reader curious, but excessive symbol usage will look like another marketing trick. That discovery might have a negative impact on the open rate. Therefore, you should aim to optimize newsletter subject lines with Unicode symbols every once in a while and not in every newsletter.

Here’s what you need to keep in mind when using Unicode symbols in the subject line:

  • Select an icon that is relevant to the newsletter content
  • Test the symbol placement in the subject and send a test email to check whether the symbol will display
  • Use symbols sparingly
  • Go for A/B multivariate testing to optimize newsletter subject lines with Unicode symbols and learn how many users react to them
Hear more from the DMA

Please login to comment.