Search engines can be a major driver of organic traffic to your website, so making sure your web pages are appropriately ranked by search engine algorithms can help you attract interested website visitors.
One way to determine what works best for your website is through search engine optimization (SEO) A/B testing. With this tactic, you’ll make a controlled set of changes to your pages, tweaking things like the content order, the terms in your meta descriptions, and the structure of commerce pages. You’ll change one set of pages while leaving another set unchanged.
This way, you can figure out which changes work and which don’t and adjust your SEO strategy based on real data rather than guesswork, improving your search visibility.
What is A/B testing in SEO?
SEO A/B testing, or SEO split testing, is the process used to test changes on your website to see which adjustments can help you gain more organic traffic. You’ll gain a better sense of what will improve your content’s rank in search results, so you can then make that change across the site to increase click-through rates.
The way it works is this: You separate your content into two groups, control and variant. The control group remains change-free, while the variant group contains changes to content or metadata. Ideally, you change only one variable at a time to help ensure you get valid results.
SEO A/B testing vs. typical website A/B testing
The SEO A/B testing process differs from typical website A/B testing that involves creating two variants of the same page and routing 50% of traffic to each. The typical process is more precise since the two pages are otherwise identical and traffic is evenly split. With SEO testing, this isn’t possible. It’s not realistic (or desirable) to have multiple versions of the same page ranking on search engine results pages (SERPs). Instead, aim to test variables on two sets of pages that are similar in search intent and authority. If your variant group consists of pages where you have low authority but your control group consists of pages where you have high authority, you’ll get skewed results.
For example, you might test two sets of comparable product pages that, historically, receive the same amount of organic search traffic. If your changes to one set lead to improved SERP rankings and an uptick in traffic while the control pages’ rankings and traffic stay the same, it’s safe to say your changes worked.
Why should you A/B test your SEO content?
There are a few reasons to conduct SEO A/B testing:
Show measurable progress
Increasing your rank on the SERP and driving organic traffic to your site can feel more like an art than a science, but well-designed SEO A/B testing can help rein in that uncertainty. By analyzing real data instead of relying on assumptions, you can make targeted optimizations that have a measurable impact.
Enhance competitiveness
Split testing can also give you a competitive advantage, especially against other sites that don’t perform similar structured testing. Consistently testing and refining your SEO strategy allows you to respond to algorithm changes and evolving user behavior faster than your competitors.
Avoid expensive errors
SEO A/B testing is valuable whether you get a positive or negative test. If your variant pages show no SEO improvement, you can avoid spending time or money on sitewide changes that won’t improve your rankings. SEO split testing helps you identify potential pitfalls early. This proactive strategy reduces risk and ensures that your SEO efforts contribute to long-term growth.
How to design an SEO A/B test
When you set out to test SEO changes on your website, the bigger your control and variant groups and the higher your current traffic, the better. Ideally, you’ll compare hundreds of similar pages with a total of 30,000 organic sessions per month or more—but this isn’t always feasible for a smaller ecommerce operation. Still, you can use the following SEO A/B testing best practices to identify page design choices that lead to increased traffic:
1. Choose the elements you want to test
You can tweak any page elements you want, from schema markup (does having more customer reviews and ratings on your site help your content appear in snippets?) to breadcrumb structure (do you want more words in the breadcrumbs, or fewer?). You might run internal linking tests to indicate which pages are significant to web crawlers. Just make sure you have a solid hypothesis.
For example, you might hypothesize that search engines want pages with affiliate links to have a disclaimer on the page—a statement saying that if a user clicks on a link, you stand to benefit financially. You can put that disclaimer at the bottom, the top, or in the middle of the page, or even right next to the link. Which works best for your site? Does the positioning on the page matter to the search engine? What about the specific language? All these variables can matter, and you can test them all individually.
2. Separate pages and run the test
Now that you know what element you’re going to focus on in your SEO A/B test, you’ll divide your pages into two groups: one for control pages, one for variant pages. On a beauty website, for example, you could choose a group of specific category pages, like lipstick or face wash roundups.
Selecting similar pages to compare increases your confidence that differences in SEO performance are based on your changes rather than external factors, like seasonality. For example, some commerce pages may gain traffic around a holiday, not necessarily due to any changes you make. A good testing strategy will take this into account and select two groups of pages that show similar traffic fluctuations around the holiday.
3. Measure the results
Generally, you’ll need to wait three to four weeks to ensure that search engine bots crawl your revised pages and that you have enough data for accurate analysis. You’ll want to compare real organic traffic from your control group against that of your variant group. If there’s a difference, then the test is likely statistically significant, which means that the result is less likely to be explained only by chance.
SEO A/B testing FAQ
What is A/B testing in SEO?
A/B testing in SEO involves choosing a specific element to change on a group of web pages, separating those pages into two groups (control and variant), and making changes to the variant pages. Running the test is intended to see if there’s an uptick in traffic and rank on the SERP due to the changes you made.
What’s an example of an SEO A/B test?
You might test pages with specific keywords in meta descriptions, differing alt text wording, or inline imagery. To do so, you’d make the change across one set of pages (your variant) while leaving a comparable set of pages (your control) unchanged. If the variant pages show improved SEO performance, your test was likely successful.
How do I know if my website is a good fit for SEO A/B testing?
You’ll need a lot of pages and traffic to make sure your results are statistically significant. You’ll generally want at least 300 pages with the same template (like product pages, blog pages, etc.), and each of those pages should drive at least 30,000 monthly organic sessions. Of course, the more traffic per page, the more reliable your results will be.
