How to boost ROI with SEO A/B Testing

Although we usually think that A/B testing is relegated to the realms of PPC or Paid Social, it can also be a great tool for more technical SEO.

Whether it’s boosting website function, overall conversions and user experience, A/B Testing can serve as a useful spot-check for content. However, you need to be careful not to overdo it as on a larger scale, A/B testing can actually pose problems for SEO activity and your site’s overall wellbeing.

In this guide, our team of in-house experts will take you through what A/B testing is through the lens of SEO, how it works and what you can do to make sure it optimises – and not tanks – your website.

First, let’s unpick how the two operate together.

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How does A/B Testing and SEO work together?

By directing traffic to two different web page versions, A/B Testing gives you the ability to see which version can give you a better result, whether that’s:

And other variables.

From here, you can easily determine what needs to be done to optimise your page, from improved CTAs to redoing your page’s UX for better visual flow. Rather than doing huge changes as a ‘one and done’ approach, we recommend that SEOs slowly alter their page to see what works and what doesn’t – growing organic visibility through measured changes.

Using A/B Testing alongside SEO strategies

It’s important to note that while A/B testing can often shed light on quick fixes – it’s exactly that. Quick.

That’s why you should always use it as part of a longer-term strategy, which implements changes that will reflect in the rankings and SERPS over a matter of months.

With this approach, you can ensure that any immediate wins from A/B testing are retained, rather than retracting from any long-term success as a result of your overall strategies.

To stop you making any catastrophic decisions, especially when it comes to the technical side of things, we’ll touch on some of the topline issues with A/B testing.

Impact on technical SEO

Illustration for AB testing

Things to keep in mind

While it’s tempting to put all your eggs in one basket with A/B testing, it can have an impact on pagespeed, which can stop you from having a reliably fast site.

If you are running A/B tests, especially multiple, you can be adding excessive scripts or heavyweight code. This can slow down page loading speeds, the results of which can majorly irritate your users, leading to higher bounce rates and a drop in rankings.

Clouded analytics and attribution

If you’re going to A/B test at scale, expect your site analytics to take a bump – so make sure to do it in realistic, bite-size chunks.

This is because a number of test variables newly introduced to analytics, as well as a number of productions released into the pipeline, can skew your data. These inaccuracies can impact overall organic search traffic and rankings, which can make it tricky for you to see the real-life impact of things like an algorithm update.

Crawling, indexing and cloaking concerns

Process of a website crawl and index

Cloaking is deemed a ‘blackhat’ practice where different content gets presented to users, which goes against Google’s main guidelines. To avoid being seen as deceptive, your A/B testing must be as transparent as possible.

Plus, a real lack of SEO management during A/B testing can result in the indexing of multiple test and control variants. This can cause duplicate content issues, authority dilution, crawl budget wastage and more – giving you even more of a headache.

Extensive crawling and processing of A/B and multivariate experiments can consume a significant portion of this budget, as search engines may expend resources crawling multiple versions of content.

Wasting your crawl budget can majorly impact your SEO efforts, meaning new and useful content will be indexed late – or simply not found.

That’s why it’s crucial to manage A/B testing in a way that isn’t going to flag as suspicious to Google or waste your crawlers.

Internal linking integrity

Any change that could impact internal linking architecture can significantly impact SEO.

That includes A/B tests that tweak even small things like link placements or navigation menus, which can all disrupt ranking factors. Even small changes could potentially stop your website from being discovered, tanking authority and key SEO performance on main pillar pages.

Keeping your website’s navigation structure as sound as possible is paramount.

Best practises

In a hurry? Here are our best tips at a glance for your A/B tests.

  • Don’t Cloak Test Pages: Don’t try to outsmart Google by showing the search engine different content than what’s being served to users.
  • Use Canonical Links: Boost – and maintain – your origin page’s SEO strength by pointing to it as the canonical.
  • Use Temporary Redirects: Use 302 redirects for test variations to avoid impacting SEO, as 301 redirects signal permanent moves.
  • Run Tests Efficiently: Run any tests for only as long as you need them to avoid wastage. Even with a little time, you can still gain statistically significant results.

The Embryo approach

Want to transform your website’s output with strategic A/B Testing? With years of experience in creating specialised content plans and SEO strategies for our clients, we know what it takes to make marketing magic.

To get key insights into your SEO – or to get your content journey started – get in touch with us today!

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