What Is A/B Testing? Useful Insights & Examples

Discover the power of A/B testing, learn its insights and see real-world examples illuminating its impact on decision-making and optimization strategies

What Is A/B Testing? Useful Insights & Examples - Clay

A/B testing (or split testing) is a popular user experience (UX) design method used to compare two versions of a website or app to determine which one performs better. It involves creating two versions of the same web page, feature, or product and then showing each version to users to measure their preferences and behaviors. The goal is to identify which version resonates most with customers so designers can make improvements to increase engagement and conversions. By analyzing data from A/B tests, UX professionals can gain valuable insights into how users interact with their products, enabling them to create experiences that are more intuitive and engaging for their customers.

Introduction to A/B Testing

A/B testing, also known as split testing, is a type of usability testing that involves comparing two versions of a product or interface - version “A” and version “B” - to determine which design performs better in user engagement and satisfaction. By running tests with different versions of a product or interface, UX designers can gain valuable insights that can lead to positive changes in the user experience (UX). With the help of analytics tools, they can observe how users interact with different elements on the same web page and compare results between versions "A" and "B." This allows them to optimize their designs with greater accuracy.

Source: Optimizely
A/B testing illustration

Benefits of Split Testing

The main benefit of A/B testing is that it provides UX designers with quantitative data they can use to make informed decisions about how they design interfaces and products for users. With this data-driven approach, UX designers can quickly identify problems in their designs and improve the overall user experience (UX) more effectively than relying on guesswork or intuition alone. Additionally, by conducting regular tests, UX designers can continuously refine their designs and improve usability.

Types of A/B Tests

There are several types of A/B tests UX designers typically use when conducting usability testing:

  1. 1.

    Usability tests involve comparing the performance metrics associated with two versions of an interface or product, such as task completion times or success rates for each version (A versus B). By tracking performance metrics for both versions, UX designers can identify which elements may be causing usability issues and make improvements accordingly.
  2. 2.

    Layout tests: With layout tests, UX designers compare how users interact with different page layouts to determine which configuration works best for their target audience(s). By running multiple rounds of layout tests over time, they can further refine their designs while increasing efficiency and productivity among users who visit the page or use the product as intended by its creators.
  3. 3.

    Feature comparison tests: Feature comparison tests allow UX designers to evaluate how well certain features perform when compared against each other on a given interface or product page. Through these experiments, they can determine which features should be prioritized to maximize user engagement and satisfaction rates across all devices used by the target audience(s).
Source: DigginTravel
A/B testing steps

Process for Implementing an A/B Test

If you want to start A/B testing, this framework is for you!

  • Firstly, collect data by utilizing tools such as Google Analytics. This will help you identify the parts of your site or app with higher traffic and optimize them more quickly. Additionally, look at pages with high bounce or drop-off rates that can be enhanced. Furthermore, take advantage of other resources like heatmaps analysis, surveys, and social media data collection when hunting down new opportunities for improvement in your website's performance metrics.
  • Establish objectives: Your conversion targets are the indicators to decide if your variation is more effective than the original. Objectives can be anything from clicking a specific button or a link to purchasing products.
  • When you have determined a target, start conceptualizing ideas for A/B testing and developing test hypotheses that explain why they would outperform the existing version. Rank these thoughts in terms of the expected effect and complexity of implementing them.
  • Utilize the power of A/B testing with Optimizely and customize your website or mobile app in ways you never thought possible. From changing the color of buttons to rearranging elements on a page template to even hiding navigation components, it can all be done quickly through an intuitive visual editor interface! Before launching any experiments, ensure that everything is exactly as desired by running a test run - this way, you'll know if things are working correctly.
  • Put your experiment into action! As soon as you do, the visitors to your page or app will be divided randomly between the control and variation of their experience. Track each visitor's journey and analyze it against the baseline to determine which performs better. Then measure, count, and compare these results for insights guiding future strategies.
  • Await the data results: To ensure your changes have a valid impact, hang tight for highly accurate and reliable test outcomes. Depending on how large your sample size is (your target audience), it could take some time to get satisfactory conclusions. Remember, high-quality experiment results will show you when they are safe and statistically significant!
  • Once you've reached the end of your experiment, it's time to review the results. Utilizing A/B testing software will provide data from your test and demonstrate any disparities between how both versions performed, along with determining if there is a statistically significant variance. It's essential to guarantee that statistically valid results can be achieved when concluding an experiment so that its outcome can be trusted.
A/B testing diagram

If your variation is a success, celebrate your victory! See if you can use the insights from this test to improve other page elements of your website and continue experimenting with enhancing results. Even if the experiment fails or yields no tangible result, don't fret. Take it as an opportunity to learn and create new hypotheses you can test.

Analyzing A/B Test Results

When it comes time to analyze results from an A/B test, there are a few key factors that must first be taken into consideration before drawing any conclusions :

  • What were the initial goals set before launching?
  • How much traffic was generated towards each variation?
  • What were user engagement rates like across all variations?
  • How did success rates differ between variations?
  • Did any unexpected trends emerge that could potentially impact future decisions?

Once these questions have been answered, it is possible to interpret the data collected thus far accurately and statistically significant results. Through this process, UX designers will know exactly what changes need to be implemented based on information provided by AB test results. It also gives them insight into how well certain features perform under certain conditions, allowing them further refine designs more efficiently over time.

Source: Smart Insights
Usage of A/B testing in companies diagram

To Ensure Successful A/B Testing, What Mistakes Should Be Avoided?

If you want to elevate your business metrics and maximize incoming revenue, A/B testing is an indispensable tool. While this process requires great planning, patience, and accuracy, skimping on any of these could harm your enterprise. To ensure that you don't make silly mistakes when running your tests, here's a list of some common missteps to remember:

Number One Misstep: Neglecting to Map Out Your Optimization Plan

Before beginning an A/B test, a hypothesis must be crafted. This initial step provides direction for the following steps and determines what should be altered, why it needs to change, and the expected results. If you establish a false assumption from the onset of your experiment or test hypothesis, your likelihood of achieving success decreases significantly.

Instead of just taking someone else’s word for it and implementing their test results as is onto your website, you should consider why not doing this may be beneficial. Every website has different goals, target audiences, traffic sources, and optimization methods, meaning that the same tactics that worked on one site may have vastly different outcomes when applied to yours. Don't forget: what was successful for them might not necessarily yield a 40% uplift in conversions for your business!

Source: Smart Insights
Most common A/B tests by testing areas

Avoid the #2 Pitfall: Assembling Too Many Variables for Testing

Industry veterans repeat one thing: don't conduct too many tests simultaneously. Examining numerous website components makes it hard to recognize which factor affected the test's achievement or misfortune. The more elements tested in one variation, the more traffic needs to be on that page to yield reliable results, so prioritizing and organizing your tests is essential for successful A/B testing!

Don't Make the Error of Skimping on Statistical Significance

When personal intuition and feelings are considered when forming hypotheses or objectives for an A/B test, it can be doomed to failure. Nevertheless, you must allow the experiment to run its complete duration so that it reaches its statistical significance - no matter how successful or unsuccessful it is. This will always provide valuable insights and help plan future tests more effectively.

The Next Mistake to Avoid: Ignoring External Factors

Tests should be conducted in corresponding periods to achieve statistically significant results and reliable outcomes. It is erroneous to contrast website activity on days when traffic is exuberant compared to when it gets the least attention due to external aspects such as promotions, holidays, and more. Since this comparison does not contemplate equal factors, there's a higher risk of arriving at an irrelevant finding.

Source: Depositphotos
A/B testing strategy diagram

A/B testing & SEO

A/B testing can significantly increase your website's search rank without risk if done correctly. However, there are some cautions that Google has outlined to make sure you don't accidentally sabotage yourself by using an A/B testing tool inappropriately (e.g., cloaking). To ensure the safety of your site and its ranking on SERPs, it is essential to follow these best practices when conducting an A/B test.

  • Abstain from cloaking: Cloaking exhibits search engines other than a traditional visitor would see. If done, your site might be downgraded or even expelled from indexed lists - this could have dire consequences for your business. To dodge cloaking and guard against it, avoid misusing guest segmentation to show Googlebot diverse content dependent on user-agent or IP address.
  • To prevent Googlebot from becoming overwhelmed and confused by multiple URLs on the same page, incorporate rel="canonical" into your split tests. This attribute will direct all variants back to their original version, simplifying the process for you and Googlebot.
  • Instead of a 301 (permanent) redirect, use 302 (temporary) when running tests to reroute the original URL to a variation. Doing so alerts search engines such as Google that it is only temporary and should keep indexing the first link rather than the testing one.

Great A/B Testing Examples

Netflix: Featured Video

Netflix is a trailblazer in experimentation, and they are widely celebrated for its thousands of tests. This information can be found on The Netflix Tech Blog. Of the most notable ones is finding the right artwork images to promote videos; this process requires A/B testing, which aims to assist viewers with selecting something entertaining and deepening engagement around each title.

To demonstrate the power of art, they conducted a test for The Short Game to ascertain if replacing their default artwork would captivate more viewers and help engage them in watching. They hypothesized that by having improved artwork that effectively conveyed the movie's narrative, it would have a broader reach and generate greater engagement from users.


Source: Netflix Tech Blog
Netflix A/B testing results

After running a split test of a variant test, the take rate improved by 14%, demonstrating that visual storytelling can be optimized to yield higher conversion rates. Have you ensured your visuals are explicitly conveying what they should be? If not, it could impede an otherwise splendid customer experience and hinder conversions.

HubSpot: Site Search

To find out which approach would bring in more engagement for their site search tool, HubSpot conducted an A/B/n test. Three different versions were developed:

  • Variant A - the search bar was placed prominently with placeholder text altered to "search by topic";
  • Variant B - identical to version A, but just limited to the blog page;
  • Variant C again features a visible search bar labeled "search the blog."

They hypothesize that by making the website search bar more visible, with appropriate placeholder text, users will be encouraged to interact with it leading to higher blog lead conversion rates.

Source: Hubspot
HubSpot search 1
Source: Hubspot
HubSpot search 2

The outcomes were remarkable! All three variants outshined the original, with variant C leading at an impressive 3.4% conversion rate and a 6.46% user engagement boost from the search bar feature.

Fill Your Bag vs. Add to Shopping Cart

If you're looking to up your e-commerce game and increase conversions, look no further than using "add to bag" on your button copy. Numerous flourishing fashion and accessories labels have adopted this phrase because it's so successful - but could it also benefit you? Don't brush off the possibility yet; investigate how “add to bag” can work magic with your marketing campaign and unique website!

Conversion Fanatics experimented with comparing "add to cart" performance against "add to bag" for one of their clients.

Control (source)
Add to bag
Challenger (source)
Add to cart

The hypothesis is that transforming the button text from “add to bag” to “add to cart” will increase the number of people who click on it and convert.


Source: Conversion Fanatics
Add to bag/cart comparison

Analyzing the data from this particular call-to-action ecommerce store, it is evident that simply changing the "add to cart" text resulted in a remarkable 95% increase in pageviews on their checkout page. Moreover, purchases and Add-to-Carts skyrocketed by 81.4% and 22.4%, respectively! This illustrates how modifying just one or two words can produce a big lift — so why not test out different shop cart button texts for your website? You never know what kind of impact small changes could have!


Ultimately, using AB testing methods when designing interfaces helps optimize user behavior and experiences across multiple platforms while ensuring products remain effective over long periods of time. As such, incorporating this testing into UX design strategies proves invaluable when striving towards creating high-quality experiences that best serve the target audience(s).

By understanding the basics of A/B testing in UX, designers can increase their chances of success when designing successful interfaces and products. By running multiple rounds of layout tests over time, they can further refine their designs while increasing efficiency and productivity among users who visit the landing page or use the product as intended by its creators. With a few simple steps, any designer can begin to understand how A/B testing works in UX and how it may help them create better user experiences down the line. Overall, A/B testing is a handy tool for developers when attempting to create optimal user experiences across different devices.

About Clay

Clay is a UI/UX design & branding agency in San Francisco. We team up with startups and leading brands to create transformative digital experience. Clients: Facebook, Slack, Google, Amazon, Credit Karma, Zenefits, etc.

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About Clay

Clay is a UI/UX design & branding agency in San Francisco. We team up with startups and leading brands to create transformative digital experience. Clients: Facebook, Slack, Google, Amazon, Credit Karma, Zenefits, etc.

Learn more

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