Make Your Emails Look Great in All Inboxes: Why Testing Matters

Here’s how to catch problems with your campaigns before you send them.

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Posted by Litmus

• 6 min read

We’ve all been there: You spend a lot of time and effort crafting the perfect email, only to learn that the email that looked perfect in your email editor doesn’t look great for your subscribers. Did your images not display in your boss’s inbox? Do your subscribed contacts complain that your email looks funky in Outlook? Does the same email look completely different in your friend’s inbox when compared to your own?

It’s a problem all email marketers face: Every email client displays your HTML email a little differently, so your emails might not look the same for every subscriber. When you encounter this for the first time, a series of questions run through your head: What happened? Does this affect all of my subscribers? And how can I prevent this in the future? Right now, your pre-send checklist includes sending a test email to your own email—Gmail, let’s say—and to your coworker’s iPhone. The email looked great for both of you, so how was that not enough?

We’re here to help you make sense of what happens when emails don’t look the same across different inboxes. We’ll also cover why sending yourself a test email isn’t enough—and how email testing can help you catch issues before you send a campaign to guarantee a great experience for every subscriber.

Not all email clients are created equal

Much like you and your coworker were not using the same email client, your subscribers will open your emails in many different email clients.

Graph of email client market share percentages

While the chart above shows the top 10 most popular email clients, there are about 1,000 different email clients out there—and they all use different rendering engines to display your email, so the code will look different. Not only that, but certain features aren’t supported across all email clients, like animated GIFs, background images, or embedded video.

Even if you’ve ensured your code is rock solid—or you’re not including some of the more advanced functionality, like HTML5 video—there are settings and issues on the subscriber’s end that could affect your campaigns further. Here are 3 things that could impact how your subscribed contacts see your email:

Image blocking
Due to an email client’s default setting or even a personal preference, images in your email can be automatically blocked for many subscribers. This setting is very common in regulated industries where corporate settings block images by default. This can be one of the largest problems that your email campaign faces, because blocked images can result in emails that don't communicate anything immediately and fail to make an impact. The images might even appear to be broken. It can be worse if you don’t have any alternative text (ALT text) set up for your imagery, because then your email simply appears blank.

Device screen size
The majority of subscribers open email on their phones, so it’s important to design your emails with mobile responsiveness in mind. If your email design doesn’t scale appropriately, it may be difficult for your subscriber to interact with your email on a mobile device, causing them to stop engaging with your campaign and possibly feel negatively about your brand. Scaling your email design isn’t an easy task, though: The market is saturated with devices that have a multitude of different screen sizes, so it can feel impossible to keep up with designs that will work with all devices.

Varying support for HTML elements
You may be building out an email with background images, custom fonts, and an animated GIF at the top, but if your subscribers are using email clients that don’t support some—or all—of those things, what kind of experience are you setting them up for? Which email clients support what design elements varies, so your email will not look the same for all of your subscribers. If you don’t have a backup for unsupported design elements in your email code, your email has a risk of appearing broken and incomplete—and that can not only affect email engagement, but your brand’s reputation as well.

How email testing can help you catch rendering issues

  • “We’ve already sent this email around internally, and everything looked fine.”
  • “We’ve been using this template for a while with no issues, so there’s no need to test this one.”
  • “We haven’t caught any errors before, so we’re good to go.”
  • “It’s too expensive and time consuming to test.”

Every email marketer has probably heard these words before. It’s a common misconception that if an email has looked good before, it always will, and testing can be viewed as a waste of time and money.

The truth is, every email deserves to be tested before every send, not only to test how the email looks in different email clients and make sure there are no broken links or images, but also to give you peace of mind. Email clients can change on you, too: They can drop updates without notice, adding or removing support for HTML attributes, and completely changing how your email looks in the inbox. A template that looked solid last month can be broken today, and without testing, you might never know.

When you test your emails before every send, you’ll be able to catch issues before your subscribers do. You can ensure that your email looks great across all email clients and devices. If it doesn’t, you can make changes and fix any issues before you hit send.

Say goodbye to those unpleasant post-send surprises that make every email marketer shudder—and lost money due to poor subscriber experiences!

Email testing means better emails—and better results

Email testing helps you send better emails and guarantees a better subscriber experience for your audience. And that’s paying off. Our research shows that brands that test every email before they send it generate an email marketing return on investment (ROI) that’s 16% higher than those that don’t test their emails at all.

So does that mean you have to send test emails to all the popular inboxes now? Sending yourself tests and manually testing your emails across all popular reading environments can easily take hours—and to be honest, it’s just not a fun thing to do. The good news is: You don’t have to.

Litmus and Mailchimp make email testing easy

With Litmus integrated in Mailchimp, we provide you with your very own device testing lab, filled with over 90 popular clients and devices, including Gmail, popular mobile email apps, and key international web clients—all available to you whenever you need them. As soon as you start a test, Litmus takes lightning-fast screenshots of your email that represent exactly what your recipients see so you can quickly identify and fix problems with your campaign before you send.

Ready to make your emails look great for everyone? Head over to the Inbox Preview section in your Mailchimp account and start testing today.

Written by Whitney Rudeseal Peet for Litmus, an official Mailchimp partner. See how to become a partner.