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Why You Should Test Your SEO Ideas Before You Ship Them

8 Min Read

Your conversion rate optimization (CRO) strategy fundamentally runs on two wheels—Search engine optimization (SEO) and A/B testing.

When you optimize your landing pages consistently to improve user experience by engaging visitors on your website, it signals to Google that your website fulfils the user intent. As a result, Google incentivizes you with a high ranking in the search.  

SEO has evolved from being a traditional keyword-oriented model to a full-blown strategy as Google keeps changing its algorithm. User intent has become one of the top factors for ranking, but at the same time, it has become challenging for marketers to predict visitor behavior while making any changes in their SEO strategy. 

Download Free: A/B Testing Guide

The logical resolution to the problem of figuring out what Google and visitors want from your website is rigorous testing of your SEO efforts.

This is good news because a) it is possible to run A/B tests without impacting SEO negatively and b) Google encourages A/B testing as long as it is done bearing in mind recommended best practices. 

In this blog post, we have covered the basics of SEO testing and how A/B testing can help you optimize your SEO efforts. 

What is SEO testing?

SEO testing enables businesses to optimize their website performance on the search engine result pages (SERPs). If you have ideas to optimize SEO for your website, you can do so by testing your ideas before you execute them at scale, which otherwise might pose a negative impact on your business if you ship the changes untested. Well-informed decisions also facilitate planning a smooth CRO roadmap in terms of both—strategy and budget. 

The big advantage here is that Google encourages you to A/B test your SEO changes. You may test pages such as product pages, category pages, and elements like meta tags, copy format and relevancy, headline, call-to-action buttons, and other SERP features. These modifications are crawled by Googlebot and help Google learn new information and assess the implications of changes on your website for ranking. 

SEO testing is different from A/B testing, as explained in the following sections.

What is Googlebot?

Google defines Googlebot as the crawler that visits web pages to include them within the Google Search index. In simple words, it is computer software or a bot that keeps learning new information on your web page and indexes the changes in Google’s database. It supports the latest JavaScript features that help them render the web pages to make ranking decisions. 

Google declared the bot as the new evergreen Googlebot. And yes, there is just one Googlebot and it doesn’t like crawling duplicate pages as duplication confuses it. Let’s understand its function in bot-based testing.

Bot-based testing

With SEO bot-based testing, you run the split URL test and assess the control and variation response in a given period. It is done either to accept and deploy the changes to similar pages on your website or reject the changes before moving on with your next experiment. 

For example, if you want to test your call-to-action (CTA) buttons to rope your visitors in organically, you can compare the copy and positioning of your CTA on your website by running a split test. The bot in such a test will be presented with unique web pages with unique CTAs that you want to test. It will crawl down the web pages to index the new information which you have presented through the test, thereby mitigating the chances of confusion for the bot. You will get the winner once the test signals a significant influx of visitors into the sales funnel, which eventually will be reflected in SERPs

On the contrary, if you want to run an A/B test for CTA copy and positioning, you present a control version to a set of visitors and a variation to another set of visitors. Here, the bot may not be able to distinguish between the two pages (until you use link attributes to your original page, as discussed in best practices below), and it may confuse your testing situation with cloaking—a practice lethal for your SEO.

A/B split testing for SEO
Image source: Semrush

How do A/B testing and split URL testing impact SEO?

Simply put, they don’t. SEO is not negatively impacted by testing activities as long as you’re not deliberately trying to confuse Googlebot. 

Also, A/B testing and split URL testing are not the same. Your visitor will land on a variation or control purely by chance in an A/B test, whereas in split URL testing, they will land on statistically similar groups of pages as tests are hosted on different URLs. So, in A/B testing, you split users to test experiences, and in the latter, you split pages with distinct experiences. 

For example, if you want to test your title tags which are key to SERPs, you can compare your title tags with SEO split testing, which will allow you to create groups of pages, say product pages, where you want to ship your changes to. These pages are categorized into unique testing groups and hence appear alike to visitors and Googlebot. This type of testing is straightforward and effective for SEO. Whereas, it gets a bit tricky in A/B testing if you don’t follow the best practices. 

Split URL testing is preferred for SEO when you need to test major changes like content format, navigation, design, etc. However, you can A/B test your SEO efforts as well keeping in mind a few factors that we will discuss in the following sections.

Automation Page Graphics V4 0 Implent Seo Testing Final
Image source: SEO clarity

Best practices for A/B testing SEO activities

Google advises stringent guidelines on SEO A/B testing if you don’t want to hurt your SEO:

  • Avoid cloaking

According to Google Webmaster guidelines, cloaking is showing one version to humans and others to bots. It’s deceptive to the search engines, bringing more harm to your website. Try always to serve the original content, otherwise, Google can demote your website.

  • Use 302 redirects

Always use a temporary 302 URL rather than 301. You may need to redirect some of your URLs to consolidate similar content pages into one or move your site to a new address.

  • Use rel=“canonical” to avoid duplication 

While running an A/B test for minor changes on your web page, always add a link attribute to your alternative URLs for your testing pages. This linking enables Google to distinguish between the original and the variation. For example, Google can index your homepage as a test variation if you want them to understand that you are running a test on your homepage. You can do so by identifying the page by using rel=”canonical”. It also signals to Google that other variations are close copies and should not be confused with the original URL.

  • Experiment runtime

Figure out what you want from the changes on the website. Since Google changes its algorithm all the time, be mindful of your test’s duration as your SEO might get affected if Google updates its algorithm while your test is running. This may, in turn,  impact the metric you are testing. Such situations certainly get you skewed test results. It is advisable not to run SEO tests for long periods, unmonitored. If you want to see the positive impact of the variation, then you may want to conclude the test and make the changes live. However, if you want to gauge the scale of impact, then wait until your test reaches statistical significance. 

Blog Banner Impact Of Ab Testing On Seo

Download Free: A/B Testing Guide

How does VWO help in running A/B tests and split URL tests without impacting SEO?

According to Google webmaster, website speed is one of the key factors impacting website ranking. The VWO Asynchronous SmartCode loads in parallel with your website, thereby having zero impact on your website load time. You can customize time-out parameters for the VWO SmartCode to execute and make sure that your visitors do not experience any inconsistent behavior while using the website. If the VWO SmartCode fails to execute within a specified time, it stops and then loads the original content of the page.

VWO Testing ensures that there is no negative impact on your website ranking while A/B testing your SEO elements. For example, if you want to A/B test some minor changes in the website, such as the copy, image, or color of a button, it usually has no impact on the page’s search result snippet or ranking. However, if you want to make changes like copy length and redesign your website, it is recommended that you follow best practices such as using query parameter rel= “canonical”.

For instance, if you have two different URLs ending with A.php and B.php, you can use the below code on B.php to avoid content duplication: 


    <link rel=”canonical” href=”http://vwo.com/A.php” />


Although Google will index both the pages, you are enhancing Google’s knowledge to consider the original A.php for SEO by adding the above code. 


SEO is a black box. Nobody knows the future of Google’s algorithms and how the search engine perceives your unique web pages. 

The closest you could get to understanding it is by acknowledging that Google is getting smarter every minute as you read this blog piece. The only way to keep your SEO game up and running in this competitive age is through consistent experimentation. 

Just like the COVID vaccines. There are so many other factors at play you can only say with some reasonable amount of confidence that you can expect the results to come out a certain way.

Kevin Indig, Head of SEO, Shopify

The only solution to crack your SEO efforts for revenue generation is to keep testing, keep optimizing!

Blog Banner Impact Of Ab Testing On Seo Bottom
Nida Zehra
Nida Zehra As a marketing professional and storytelling enthusiast, I prioritize understanding data and insights over everything else while crafting a new story for experimentation. Besides work, you can find me reading fiction and, at times, metamorphosing into an artist through some discerning sorcery, which leads me to maintain an art and poetry blog on Instagram. Towards an innate linguistic inclination, I am currently looking forward to learning Persian to read and understand layers of the 14th-century Iranian poet Hafez's work—one of my most treasured literary possessions.
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