The content of your emails and SMS messages—everything from images to copy to offers to CTAs—is the element that really drives engagement and conversions.

Imagine you’re launching a new product and you’ve created two versions of campaign emails: one with a bold, image-heavy design and the other with minimalist, copy-focused design. Running A/B tests on your marketing campaigns lets you drill down into the specifics of what resonates most with your audience—and Klaviyo can help you do it by testing subject lines, offers, CTAs, and more.

Once you select a portion of your subscribers to receive your test campaigns, Klaviyo’s A/B testing machine learning capabilities determine which variation will best engage your audience—so you can use that one within your marketing efforts at large.

Klaviyo AI even has advanced A/B testing that takes your marketing experiences from one-size-fits-all to individualized. With personalized campaigns AI, Klaviyo identifies profile patterns that predict which version each individual customer is most likely to engage with—and sends that version to them, instantly.

In Klaviyo, a flow is a sequence of automated messages—sent over email, SMS, mobile push, or all 3 channels—that’s triggered by another specific action, like a subscriber joining a list or segment, making a purchase, or abandoning a cart.

When you A/B test content within your flows, you can fine-tune your automated messages for maximum impact.

Klaviyo’s smart A/B testing uses AI to help you determine which versions of flow messages generate the most clicks or orders. It identifies the best content for the majority of your audience, then automatically directs traffic to the winning variations as it gains more confidence in the test results.

Sign-up forms are often the first interaction with a potential customer in which you receive zero-party data—information your audience provides directly. And that means sign-up form design and content both play a critical role in conversion rates.

Klaviyo AI helps you A/B test different form designs, display options, and incentives to discover which combination leads to the most submissions. AI even finds the best display time for your form, and sets it live once the optimization test is complete.

Let’s say you need to A/B test two versions of a pop-up form: one with a simple email address field, and another that asks for first name, email address, birthday, and product preference. Klaviyo AI analyzes which version yields a higher completion rate at the point of statistical significance, then automatically sets that winning version live.

Subject lines play a serious role in determining whether your readers open your emails. And finding the right ones through A/B testing can significantly boost your open rates.

Let’s say you’re running a sales promotion. You know you want to create a sense of urgency for this limited event, but you’re not sure which phrasing will inspire your audience to really act.

When using Klaviyo for A/B testing subject lines, you can generate and test multiple subject lines simultaneously and use the results to refine future campaigns and flows. You can also generate subject lines with AI, see your best-performing recent subject lines, and better understand what works for your audience.

Imagine you want to see if your campaign emails have a greater impact in the morning or afternoon. A/B testing different send times allows you to identify when your target audience is most active.

You A/B test one campaign at 10 a.m. and the other at 3 p.m. Klaviyo AI evaluates the open and click rates for both variations and determines that your target audience is most active in the morning.

Klaviyo helps you test your email and SMS send times so you can dial in on engagement. By reviewing your A/B test history in the “experiments” section of your Klaviyo account, you can easily track your tests’ performance and determine which times of day yield the best results for your campaign messaging.