A/B Testing Ideas & Examples for Email Marketing

white mobile phone on blue next to black cell phone over yellow to denote A/B testing email

A/B testing is the method email marketers use to test out their ideas, strategies and tactics so they can fine tune them. This helps ensure the effectiveness of campaigns going to market are optimized.

For most email marketers the core testing ideas focus on tone, content and imagery. These types of tests will not only help you send more engaging emails, they’ll also improve your understanding of your audience.

If you write a subject line that has a high open rate, do you know whether that is optimal or you can improv eon it with slight changes. The best way to check is A/B test variations of the content to see what performs well. Marketing automation tools built for email marketing help scale these sort of tests and allow growth of the program for better ROI.

If you learn what kinds of things your audience better responds to, then you can incorporate these themes into more of your marketing.

Fundamentals and types of A/B testing for email marketers

A/B test the tone of your email message

Changing the tone of your emails can affect your response rates. The best places to test different tones are the subject line and preview text.

Both of these email components are short spaces that have a big impact on your audience. Tone can therefore be a powerful tool to increase your open rate.

The most impactful way to A/B test tones in subject lines is to test two different tones against each other.

For example, you could test a negative vs urgent subject line: ‘Don’t Be the Only One Without This Bag’ vs. ‘Today Is Your Last Chance To Buy This Bag.’

It is also important to note that different segments in your audience may respond differently to various tones. Your High Rollers might be more likely to open an exclusive tone whereas your Nearly Theres might respond better to urgent tones.

Here are some different tones that you can try testing against each other (with subject line examples):

  1. Positive
    • Our bedding is like sleeping on a cloud
    • Sleep more comfortably at night
  2. Negative
    • You’d be a fool to miss this deal
    • You’ll regret not buying these sheets
  3. Urgent
    • Today only – don’t miss out
    • This amazing offer expires in 24 hours
  4. Suspenseful
    • We have a surprise in store for you
    • Shhh… what’s inside is a secret
  5. Direct
    • It’s summer — that means t-shirt weather!
    • It’s time to replace that old t-shirt!
  6. Exclusive
    • Just for you – Acme sheets are an amazing deal
    • Not everyone has early access to Acme sheets

By A/B testing tones, you can help identify how to best talk to your different segments across your marketing deliverables.

If you try similar tone subject line tests on different segments, you can easily see which groups respond better to each tone.

This can then lead you to incorporate more of those tones into your marketing for different groups which can help increase engagement overall.

Lastly, it is important to note that not only do different tones work better or worse for your specific audience segments, some are more appropriate for specific types of emails.

For example, urgent or negative tones may increase open rates in Abandoned Carts or Browse Abandonment flows (triggered emails), but are not the best choice for Welcome Series.

Conversely, direct or positive tones might work better in Welcome Series but not in an Abandoned Cart.

This can be pretty specific to your business and audience.

Therefore it is important to test different types of tones across your different flows in order to really optimize your emails and understand your audience.

Start using an email marketing platform for better analysis and testing results

Change the imagery of your email

You’ve probably heard that images are good for marketing. There is a lot of research around the power of imagery, so it’s is crucial to test your visuals. The right images in the body of your email can drastically improve your click rates.

Similar to tone, you may find that certain types of images work better in specific email categories than others.

For example, in an Abandoned Cart series you could run tests around how you present images of your products: eg. image of the product by itself vs an image of a person using the product.

In a Welcome Series, it might be useful to test the amount of imagery you use – eg one big image vs several small ones.

Here are some ideas for image-based tests you can run:

  1. Professionally shot images featuring models using or wearing your product

2. User generated images of customers using or wearing the product

3. Just a single large image vs multiple small images

4. Image placement, including

5. At the top of the body copy

6. In between two paragraphs

7. At the bottom of your email

8. Multiple smaller images

9. This is another one where you can test image placement

10. Several images in a row

11. Images throughout your email
Multiple small images of home goods and products

Images with copy overlays

The product by itself

Understanding the kinds of email images your audience engages with in emails will give you insight into the kinds of images you should use in social, banner ads, and other marketing.

Beware – not all images are created equal! As with all good marketing, relevance and authenticity are key. Generally, very obvious-looking stock photos can actually decrease the performance of an email.

A customer of VWO showed a 161% increase in conversions just by switching from a stock photo to a real photo on their website. Choose your images wisely, and then optimize through testing.

A/B test your email content

The body of your email is where you have the most flexibility test. In this part of the email, the tests you run most directly affect clicks and conversions.

It’s crucial to test your email content to make sure it is having the biggest impact for your specific audiences.

The types of content tests you can run include:

Brand-illuminating personal stories

Many of our top performing brand-focused emails include personal stories that build an emotional attachment to your brand and differentiate your company, including brand origin and company mission.

Highlighting your different value propositions

Testing value propositions against each other can help you see which of your audience segments respond best to each value, including




Mass market appeal




Customer recommendations

If this is successful, you can then add more nuance to this test by then testing recommendations about different value propositions, price, quality, etc.

Product reviews

Similar to customer recommendations, you can build out additional tests around different types of reviews

Third party awards or recommendations

References to influencers who use your product

The history of your items

Where did the design for your products come from

What was the inspiration for the item

Email from your founder or CEO

You can A/B test content to figure out the messaging that most resonates with your different audience segments.

For example, first time buyers may be more interested in customer testimonials than repeat buyers.

Once you’ve segmented your first time buyers, you can further test the best types of customer testimonials to present: testimonials about price vs testimonials on quality.

For your repeat buyers, you could instead test copy focused on product uniquenesses or product mass market appeal.

This holds true for autoresponder email series as well.

In your Welcome Series, you can test to see if content focused on your company’s brand story performs better than copy focused on the history of your products.

In your Abandoned Cart emails you can test various product value propositions. If you find people respond more to your copy about price competitiveness than the luxuriousness of your items, then consider using that type of content more frequently on your website.

Understanding what type of messaging really resonates with your audience segments throughout the funnel will help not just with email, but with your marketing overall.

A/B testing can almost function as a customer survey, allowing you to hone in on the best messaging for your audience.

Go forth and test!

Content, imagery, and tone are three strong themes to start building A/B tests around.

Once you start understanding what your audience responds best to, you can add that into more of your marketing or create additional segments.

The more targeted your marketing, the more likely you are to see an increase in engagement and revenue!

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