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SEO Split Test Result: Small H3 Change, Big Click Result

Digital marketing experts repeatedly emphasize the importance of Search Engine Optimization (SEO) for your websites. As Google and other search engines continually update their search algorithms to improve search results, so should you improve your website to rank higher on the Search Engine Results Page (SERPs). Now, how do you determine which changes will help improve your page’s ranking? You can conduct an SEO split test.




A statistical SEO split test, also called an A/B test, is an SEO experiment conducted to determine the impact of a website change on a key SEO metric. It is done by splitting pages with similar intent into two groups—Control and Variant. Changes are made on the Variant pages and the effect on the SEO metric is compared with that of the Control page. The objective is to discover changes that would lead to improvements in click-through rates (CTR), organic traffic, and keyword ranking positions.


The scientific process of split testing may be divided into the following steps:

  1. Pick a variable to test

  2. Identify your goal

  3. Set a hypothesis

  4. Split your pages into two groups - Control and Variant

  5. Make the change to the Variant pages

  6. Report on your test results


The statistical SEO split test helps in determining the possible effect of website modifications before implementing major changes.


SplitSignal (@SplitSignalhq) shares on Twitter that they used an SEO split test to determine whether header tags are important for SEO. They decided to conduct a test on a nationally known stock image and photography website.


The variable they tested was the H3 header tag, and the goal was to determine whether a change in the H3 header tag would result in any changes in the CTR. The hypothesis was that changing the H3 tag to "Related photo searches" would increase clicks on the Variant pages. A total of 3,500 photos and images were included in the SEO split test. For the Control group, a total of 1,707 photos and images were assigned and the H3 tag "Related Tags" was used. For the Variant group, 1,793 photos and images were assigned and an H3 tag of "Related photo searches" was used. There was a significantly relevant positive result. Overall, the Variant pages received 27% more clicks during the test period, a gain of 1056 clicks. It can be concluded that minor changes in H3 tags increased clicks.


A similar result was observed in the SEO split test conducted by RankScience on Coderwall. In this experiment, they modified the title format of the post by adding the word [Example]. This simple addition resulted in an initial increase of clicks from Google by 14.8%. Coderwall then decided to implement the change, which resulted in an approximate increase in CTR of 59%.


How are these studies significant for your business?

First, it shows that while it is important to implement SEO on your pages, it is also wise to conduct experiments to measure the effectiveness of your SEO strategy. Experiments such as the SEO split test can help you do comparative testing of the effect of a specific change on specific SEO metrics before implementing the change on all of your web pages.


Secondly, the experiments conducted by SplitSignal and RankScience also show that H3 tags matter greatly to the users, as reflected in the increase in CTR. CTR (Click-Through Rate) is calculated as the total number of clicks on the link divided by the total number of times the link was displayed, called impressions, multiplied by 100. CTR informs you about the performance of your pages that are ranking in the SERPs. An increase in CTR is viewed by most search engines as a good indication of the relevance of your pages, which ultimately leads to a higher rank in SERPs.


Conducting an SEO split test allows you to make hypotheses and learn more about your users’ intentions. The change you should implement should align with your own users’ intent to yield an improvement on a defined SEO metric.


Final Thoughts

These experiments, conducted using SEO split tests, have shown that even seemingly insignificant changes do matter. Minor H3 tag improvements can lead to an increased CTR. As search engines improve their algorithms to respond to the ever-changing needs of users, websites will need to be updated proactively as well. A Statistical SEO split test is a scientific method that helps test the ability of a webpage change to affect an SEO metric.


SEO split testing may sound simple, but it takes a more in-depth understanding of SEO and your users to be able to effectively conduct this experiment. Let us handle this task for you. Let Wise Marketing Professionals share with you their digital marketing expertise to keep your business pages optimized while you focus on growing your business.


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