A/B Testing Your Emails: What to Test and Why It Matters
You’ve crafted the perfect email. The design is slick, the copy is compelling, and the offer is irresistible.
But… your open rate is low. Your clicks are even lower. And you’re left wondering:
What went wrong?
Here’s the truth: Even the best emails can flop without testing.
That’s where A/B testing (also known as split testing) comes in. It’s one of the smartest ways to improve your email marketing performance—without guessing what works.
In this post, we’ll break down:
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What A/B testing actually is
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Why it’s a game changer
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What elements you should test
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How to get started (even if you’re a total beginner)
Let’s dive in.
What Is A/B Testing in Email Marketing?
A/B testing is the process of sending two versions of the same email—with just one change—to a small segment of your list.
Then, you compare the results to see which version performs better.
Once you have a winner, you send that version to the rest of your subscribers.
Think of it like a mini-experiment that helps you optimize every email you send.
Why A/B Testing Matters
Here’s why every business should be testing their emails:
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More opens, clicks, and conversions.
Even small changes can lead to big improvements. -
Better understanding of your audience.
Learn what tone, design, and offers your subscribers respond to. -
Data > guessing.
No more “hoping” your email works—you’ll know what works. -
Higher ROI over time.
Your emails will get more effective with every test.
Bottom line: A/B testing helps you send smarter emails—and get better results.
What to Test in Your Emails
Here are some of the most effective elements to test:
1. Subject Lines
Your subject line is your first (and often only) chance to get your email opened.
Test:
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Length (short vs. detailed)
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Tone (curious, funny, urgent)
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Emojis vs. no emojis
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Personalization (first name, location, etc.)
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Questions vs. statements
Example:
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A: “Is this your next big opportunity?”
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B: “Claim your free strategy session today”
2. Preview Text
That little sentence under the subject line? It can make or break your open rate.
Test:
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Including vs. not including it
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Complementing or expanding the subject line
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Creating curiosity vs. providing clarity
Example:
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A: “Here’s how to get 3x more leads—fast”
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B: “This simple tweak helped me triple my subscribers.”
3. Call-to-Action (CTA)
Your CTA is what drives clicks—so make it count.
Test:
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Button vs. text link
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CTA copy (e.g., “Buy Now” vs. “Get Yours”)
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Placement (top, middle, bottom)
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Color and size of buttons
Example:
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A: Button that says “Book Your Call”
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B: Text link that says “Let’s schedule your strategy session”
4. Email Copy
Small tweaks in your writing can change the way people respond.
Test:
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Length (short and punchy vs. long and detailed)
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Tone (conversational vs. professional)
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First-person vs. second-person language
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Including testimonials or not
Example:
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A: “Here’s why I built this offer”
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B: “Here’s why our clients love this offer”
5. Images and Layout
Visuals can affect both engagement and load time.
Test:
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With vs. without an image
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Different header images
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Button placement or design changes
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One-column vs. multi-column layouts
Pro tip: Always test mobile responsiveness too—more than 50% of emails are opened on mobile!
✅ How to Run an A/B Test (Step-by-Step)
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Pick one variable to test.
Only test one thing at a time to keep results clear. -
Create two versions of your email.
Keep everything the same except for the one element you’re testing. -
Send to a small portion of your list.
Most platforms let you A/B test 10–20% of your audience before sending the winning version to the rest. -
Measure the right metric.
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Subject line test? → Track open rate
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CTA test? → Track click-through rate
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Offer/copy test? → Track conversion rate
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Apply your learnings.
Use what you learn to improve future campaigns and keep testing!
A Few Final Tips
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Test consistently. Don’t just test once—make A/B testing a habit.
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Track results over time. What works once might not always work again.
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Keep it simple. The best tests are clear, focused, and based on real goals.
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Trust the data. Even if the results surprise you, go with what your audience is telling you.
