How to Prevent A/B Testing from Slowing Down Your Site

A/B testing is a powerful tool for marketers, but it can also lead to slowdowns on your site. Here are some ways you can avoid these problems and keep your site running smoothly.

The problems with a/b testing is a problem that many websites face. The A/B Testing slows down the website and can cause issues for users.

You’ve undoubtedly used A/B testing tools like Google Optimize to improve conversion rates on your site.

These tools enable you to test content by randomly displaying users various versions of the same page. 

A/B testing saves time and money by preventing websites from creating features that aren’t popular with their customers. 

A/B testing, on the other hand, may sometimes result in a slower user experience if the page takes too long to load.

This often occurs when material is checked too frequently or when programming is utilized in a manner that slows down the site.

Users may leave your site if it takes too long to load, raising bounce rates and decreasing your chances of converting them. 

We’ll go through ways to avoid A/B testing from slowing down your site in this article, utilizing techniques like:

  • ensuring that the scripts are directly put into the top of the head tag, rather than utilizing a tag manager 
  • implementing Google Optimize’s asynchronous GTM version 
  • It is possible to employ animations to avoid test experiences from loading too slowly and disrupting the user experience.

Let’s get this party started.

How Can A/B Testing Make Your Site Slower?

A/B testing may add an additional step to the loading and viewing of web pages.

This occurs when visitors are given two copies of material at various intervals, gathering data on which page works better.

All of this back-and-forth communication may cause a delay in the loading of pages.

It may also result in a flash of original content (FOOC), which appears for a brief period of time before the page finishes loading.

A/B testing causes your site to slow down in three ways:

  • making your site’s loading time longer than usual 
  • producing a negative user experience that leads visitors to abandon the site or prevents them from returning later 
  • Because pages are taking longer to load and display, any additional events, such as an email campaign, are being postponed.

The time it takes for a page to load is an essential statistic for conversions and SEO.

According to studies, the first five seconds of a page’s load time have the greatest influence on conversion rates.

Similarly, 70% of customers believe page speed affects their purchasing decision.

Finally, you must ensure that your site is quick if you want people to remain on it and buy your goods. 

google on bounce rates for sites to prevent a/b testing from slowing down your site

How to Avoid A/B Testing Slowing Down Your Website

To avoid A/B testing from slowing down your site, additional precautions must be taken to guarantee that the user experience is not harmed.

Backlinko claims that the average page load time on desktop is 10.3 seconds and 27.3 seconds on mobile.

You may have an issue if you aren’t hitting these marks.

There are a few things you can do to keep your site from slowing down, whether you’re using Google Optimize or another A/B testing tool.

How to Prevent A/B Testing From Slowing Down Your Site

1. Scripts should be used at the top of the head tag.

If you’re going to add A/B testing scripts to your site, make sure they’re at the top of your head tag rather than a tag manager.

This is essential since the scripts will be overridden if you make modifications to your site.

When you make modifications to your website, a tag manager is an external script that loads in place of others, overwriting them without notice and preventing scripts from working correctly.

Make sure the synchronous version of the script is put after your site’s scripts if you’re using it. 

This will eliminate any issues created by third-party resources on your website, such as ad networks, causing delays. 

2. Take use of asynchronous tracking

There are two versions of Google Optimize: synchronous and asynchronous. 

The synchronous versions don’t allow any material to be rendered before it’s completely loaded. This may make it difficult for your A/B tests to load in a timely manner. 

The asynchronous versions delay the rendering of any content until it is ready, but they do not block the execution of other scripts on the page.

For the most part, the asynchronous version is preferred. It runs on a different thread from the rest of the website, so it doesn’t interfere with the execution of other important activities.

While the async version prevents some animations from slowing down your test sessions, other components on the page will continue to play.  

If you’re using a tag manager like Google Tag Manager (GTM) or another JavaScript management system, make sure you use the asynchronous version of the Optimize snippet instead of the regular version.  

When Google Optimize is enabled on your website, there should be no delays in page load time. This may be avoided with the async version by adding asynchronous to each script call so that it does not impede rendering.

This is especially essential if no tests are performed or if they are run in a non-interruptive way across all pages.

3. Use animations to improve the user experience.

If you’re using Google Optimize, you can also utilize animations to avoid slow-loading test experiences from disrupting the user experience.

By providing visitors something enjoyable to concentrate on while they wait for information to load, animations may help avoid A/B testing from slowing down your site.

For example, before a site completely loads, you may utilize animations to keep visitors interested, as seen below.

How to Prevent AB Testing From Slowing Down Your Site Incorporate Animations

Users will be notified that their material is being loaded, and they will be unable to leave the page.

Always remember to center your animations in a location where your user’s attention will be drawn.

A loading page, or a page where the user will be focused on a particular area of the design, is an excellent illustration of this.

Remember to keep animations from interfering with other tests and to make sure they’re working properly on all pages.

4. Snippet Size Should Be Reduced

Try to make your snippets as short as possible when adding them to your site.

This will prevent the script from slowing down other sections of your site, as well as delaying or interrupting other scripts on your page. 

You may accomplish this with the help of a tag manager like Google Tag Manager (GTM). 

GTM will enable you to shorten the snippet or just include it on certain pages. 

If you simply want to apply it once across all of your page’s head tags, you don’t need to use a tag manager with Google Optimize. 

If you want to directly embed the script into each page, make sure it is placed at the top of the head tag. 

5. Perform server-side testing

The latency is typically considerably less apparent when running A/B testing on separate server sides. 

On the client side, for example, you could utilize PHP instead of JavaScript to avoid content from loading slowly and disrupting visitors who are testing out your new site design. 

Using separate server sides works because the async version prevents browsers from stalling on a callback function, preventing all other content from loading while the code is being executed. 

The advantage of doing so is that server-side testing minimize content loading delays for users with poor connections or excessive latency. 

If you can’t do this, use Google Tag Manager to load these scripts asynchronously, so they execute after the page is rendered and don’t slow down the page. 

Keep in mind that since there is no mechanism to bring asynchronous JavaScript into service while testing on separate server sides, it may be more difficult to avoid users from being interrupted by a delayed loading experience. 

6. Optimize and Consolidate Variation Code

A/B testing may be made faster by consolidating and optimizing variant codes. 

The code that Optimize uses for each variant is called a variation code. 

The more complex your website is, the more variants you’ll need to develop, and the more often these tests will run, slowing down your site. 

If too many modifications are made to a page at once, other scripts may be unable to execute correctly, or the page may not load at all.

This degrades the user experience and prevents you from further improving your website via testing. 

For example, if a user has JavaScript turned off or disabled, they may never see the variant with optimized content for them, which can cause improvements to be delayed by many weeks!

This is why it’s critical to place all of your Optimize scripts and codes in the head tag of your website.

7. Keep all of your information in a single file.

Your website has a lot of data and assets that must load before a visitor can see the page. 

These assets and data must be exchanged across the two experiences when running an A/B test, but they may also create a lot of problems if they aren’t properly handled. 

Let’s suppose your previous site utilized Font Awesome for all of its icons, but your new site utilizes Google Fonts since it’s more web-friendly. If you’re conducting an A/B test on your website, your old site must utilize the same Google Fonts as your new one. 

Because all of these additional assets are loaded on top of one other, if you don’t handle this properly, it may create a significant delay in how quickly the page appears for visitors. 

Keep all data in a single file to avoid A/B testing slowing down your site. As a result, the page will not have to make repeated requests for information. 

All of your experiments should be kept in one location where everyone on your team can readily access them. This may help you avoid a lot of problems while also making it much simpler to monitor the progress and results of each test you’re conducting. 

Frequently Asked Questions About How to Avoid A/B Testing Slowing Down Your Website

Is Google Optimize causing your site to load slowly?

Google Optimize has a little impact on page load times. What matters most is the amount of time it takes for your website to load, as well as latency and visitor connection speeds.

After an A/B test, what should you do?

After you’ve finished your A/B testing, you should evaluate the results and take action depending on what you’ve learned. It’s also a good idea to plan a fresh A/B test so you can keep learning.

How can I make my Google page load faster?

Page performance is determined by a variety of variables, but improving your A/B tests may help keep your site from slowing down.

When should an A/B test not be used?

You shouldn’t utilize an A/B test if you don’t have enough traffic, don’t have the time or resources to devote to testing, don’t have a hypothesis to test, or don’t require additional traffic.

Conclusion on How to Prevent A/B Testing from Slowing Down Your Site

A/B testing is a powerful technique for increasing conversions, and it’s something that every website owner should do. 

Understanding how to keep A/B testing from slowing down your site, on the other hand, is crucial since sluggish test experiences are inconvenient for users. 

Sites that successfully utilize A/B testing will notice an increase in traffic as well as better audience insights. 

How have you utilized A/B testing to boost the performance of your website?

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A/B testing is a method of determining which version of your website or app performs better. This process can be time-consuming and slow down the performance of your website. The multivariate test calculator will help you to prevent this issue by calculating how long it will take for the test to finish.

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