Performing A/B testing (or split testing) is a great way to find out what works best for your emails and landing pages. A/B testing allows you to optimize your emails and landing pages to maximize conversions. So basically, your goal is to increase the effectiveness of your marketing efforts.
In an A/B test you test an original version of an email or landing page against other versions (or variants) with a single element changed. This is different than Multivariate testing, in which you test multiple elements of an email or landing page. For example, you could A/B test your email subject line to see which one results in a higher open rate. Or you could test the color of your call-to-action button on a landing page to determine which one attracts the most clicks.
For A/B testing emails, you send each variant to a percentage of your contacts. Say your sample size is 100,000 people, you can send the original email (version A) to 25,000 people (25%) and version B to 25,000 people (25%). A winner is determined based on your desired metric (most opens or clicks) and then that winning version is sent to the remaining 50,000 people (50%).
For A/B testing landing pages, a percentage of traffic is randomly directed to each variant. So again, if your sample size is 100,000 people, you can split the traffic 50% (50,000 people) to the original page and 50% (50,000 people) to version B. The winner is then again determined based on the metric you choose (most visits or clicks).
You should have a goal in mind when conducting A/B testing, whether it’s getting more people to open your email or getting more downloads on your landing page. Also, it’s best to let the test run long enough (at least several hours) to gather significant results. In addition, make sure your sample size is big enough to obtain meaningful results.