How do you test and measure the impact of emojis on email open rates?

I would however caution using OPEN RATES as the metric to track as, since the iOS 15 update, they'll be inflated by false positives. generated by the Apple Privacy Protection. It may be best to consider excluding Apple from any tracking of open rates - but that's a huge chunk of your metrics so may not work for everyone. Instead, consider looking at CLICK RATES (as a % of emails received). Whatever you choose - make sure you look at past campaigns and create some benchmarks to support the way you analyse current and future campaigns.

Expecting an emoji to increase your open rate by 56% is a bit far fetched to me, but I do believe they can provide some kind of lift still. When I look at my inbox, less than 30% of emails use an emoji, so you can still use them to draw eyes to your subject lines with color. They also present an interesting opportunity for branding if you use the same emoji over and over again (think Morning Brew). Over time, if every brand uses them, their impact will diminish.

Using emojis in emails can be a powerful way to help set the tone of your message before the recipient even opens it. Emojis can convey emotions that might be difficult to express with words alone. For instance, a smiley face can create a friendly, approachable vibe, while a sun might suggest positive news or a summer sale. This visual communication helps to immediately convey the mood or feeling behind your message, aligning the recipient’s expectations with the content of the email.

I have personally A/B tested emojis in at least 30 email subject lines throughout my career. And not once have including emojis resulted in a meaningful lift in open rates. Testing them in the body of an email, however, has resulted in higher clickthrough rates. By strategically placing emojis near your CTAs, you can draw attention to a button or link and increase the rate at which that CTA is clicked. So don't waste your time A/B testing emojis in subject lines, but DO use it to figure out the best placement in the body of your emails.

The colour of emojis matter too. Red and yellows stand out. Users on light mode or dark mode might have some emojis blend into the background.

Make sure to research other meanings of the emojis you plan to use as many have alt meanings you wouldn't want associated with your brand.

Keep it to just 1 emoji in your subject line. Otherwise, you risk coming across as spammy or unprofessional and potentially being sent to the spam folder. Use them through a lens of inclusivity, ensuring they're appropriate for diverse audiences. Consider your audience...if the context is professional and/or your audience is traditional, emojis may be off-putting. And last, A/B test performance to monitor how your audience is or isn't engaging.

An example I've seen be highly effective is the use of emojis for branding purposes. Effectively associating one or two emojis to your brand can automatically help your audience identify your emails in a full inbox. I've seen one brand use the lightening bolt emoji in their subject lines ?. This symbol is used across their marketing, so their emails always catch my eye and drive me to open, regardless of the subject line.

I've seen great success using emojis, such as the eyes emoji, in abandoned cart subject lines. However, be wary of using warning or alert-type emojis in subject lines. These can annoy or offend recipients by creating a false sense of urgency over something they may find insignificant. Such use could be perceived as manipulative, potentially undermining trust in your communications.