Email testing is imperative in today's marketing landscape. Your audience's attention span is decreasing day by day, and an opportunity to communicate with them directly via email is highly advantageous to marketers.
Can you afford to send out anything but the best version of your email? Not really. You need to send emails that convert leads and don't end up in spam. That's where email testing comes in handy.
Table of contents
What is email testing?
Email testing is the process of inspecting various aspects and elements of your email to optimize KPIs like open rates, CTRs, etc. Email testing helps you improve email deliverability, rendering, and even the quality of your subject lines and email content that resonates with your readers.
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What should you test in an email?
There are three main factors to testing an email - Content validation, Campaign parameters, and Technical validation
1. Content validation
This deals with the testing for the subject line, preheader text, and CTA.
The subject line is critical to the success of your email campaign. It's the first thing your audience reads that could get them to open your email or ignore it. It needs to be catchy and of value to the reader. How do you know if your subject line is working? Test for higher open rates.
Types of subject lines to test for:
Short copy vs. long copy
First name personalization
Tone – informal vs. corporate
Discount vs. free value-added conveniences
Copy optimized for mobile vs. desktop or other devices
The preheader text is the content that appears beside the subject line in your mailbox. It's the first line of text in your email that you can see right below the subject line (or beside – in the case of the desktop). It is the wingman to the subject line, providing context on what the email is all about.
The preheader text can also boost your open rates. It's like the wrapping paper on the gift. They set the mood for what a subscriber can expect upon opening the mail.
Variations to test preheader text in an email:
Include vs. exclude the preheader text altogether
Highlight different topics, especially if it's a newsletter
Elaborate on the subject line: for example, if the subject line is a question, then arouse the curiosity of the reader
Call to action
The CTA is usually designed to be the center of attention of each email. Here's what you can test in your CTA:
Generic vs. specific copy. For example, "Learn more" vs. "Get the look-book now"
Colour of the CTA can inspire us to take immediate action, like red or orange
Top vs. bottom placement of the CTA
Size of the CTA button
Different offers or promotions
Split test your emails for the subject line, preheader text, and CTA.
2. Campaign parameters
Here, your email is tested for the email scheduling time and date
Email scheduling time
Test your email scheduling time to ensure more productivity.
Testing the email scheduling time helps you understand at what time of the day your audience is more inclined to click on the CTA and make a purchase instead of quickly scanning through the mail and "saving it for later."
Email scheduling date
Test the email scheduling days to see the change in your open rates and CTRs.
Both the email scheduling days and time need to be tested regularly to find the sweet spot of the highest open rates and CTRs. There's no correct answer to it as it may change from season to season, business to business, and place to place.
Read how our client Project Pro achieved 3X open rates by improving their email deliverability.
3. Technical validation
Aspects like design and layout, HTML and CSS, Font, links, and images are tested here.
Design and Layout
The viewing experience is key to getting more conversions. The design and layout of an email can determine whether the subscriber will scroll down and click on the CTA. Test the design and layout of your emails regularly to improve the viewing experience and CTRs.
Use A/B testing on your email service provider for this.
HTML and CSS validation
Factors like ESPs, operating systems, screen sizes, images, app, and web-based email clients affect email rendering. Each email contains some HTML code, which can be displayed differently on various devices due to the reasons listed above.
As most marketers use responsive email builders, few think of testing and validating the HTML code.
Font, link, and image validation
Unclear font, broken links in your emails, and blocked images can hamper your viewing experience, eventually leading to more and more unsubscribes.
There are many other elements you can test for.
Why should you test your emails?
Email testing allows you to compare various elements to see how each one affects your subscriber's behavior. Whether a more compelling subject line can boost open rates or a differently colored CTA button can drive conversions – you can find out only by email testing.
Here's why you should test your emails:
Email testing helps in boosting open rates and conversions.
It helps in understanding subscribers' behavior and what resonates with them.
It helps you create and send technically sound emails that are correctly displayed on all devices.
By testing your emails, you can send emails that don't end up in spam.
It helps you create well-designed emails with an easy-to-follow format.
Checks domain reputation.
Improve deliverability and other KPIs.
Related guide: 9 Reasons Why Your Emails Land in Spam and What You Can Do About It
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How to improve your email testing?
There are many ways in which you can improve your email testing. Some of the main one's are listed below:
1. Know what you're testing and why:
Email testing is pointless without a goal. Use a statement template like “Changing
2. Test one element at a time:
If you test more than one aspect of your email at a time, you won't be able to determine which variant drove the success.
3. Avoid testing large groups:
Testing smaller groups gives you a clear winner, which can be incorporated into your larger mailing list.
4. Maintain a testing schedule:
Run tests on the same day of the week, at the same time. This helps avoid the timing variant affecting your results.
Don't guess. Test your emails
Email testing is not a one-time thing. You must test again and again and take action on your results. And once you build your emails based on the test results, use Mailmodo to create interactive AMP emails.
What you should do next
Hey there, thanks for reading till the end. Here are 3 ways we can help you grow your business:
Talk to an email expert. Need someone to take your email marketing to the next level? Mailmodo’s experts are here for you. Schedule a 30-minute email consultation. Don’t worry, it’s on the house. Book a meet here.
Send emails that bring higher conversions. Mailmodo is an ESP that helps you to create and send app-like interactive emails with forms, carts, calendars, games, and other widgets for higher conversions. Get started for free.
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