9 A/B Testing Stats for 2021

9 A/B Testing Stats for 2021

A/B testing tools are a way for companies to make more money by putting forward the best version of their websites, emails, ads (etc.) possible. Testing two designs and seeing which one drives the most traffic allows companies to ensure that the content they put out will result in the most engagement possible. 

A/B testing can also help examine user behavior on web pages. With data from A/B testing, companies can determine whether they should stick to the status quo, or if changes couldincrease their conversion rates and engagement. For example, something as simple as a red or green button could make a 21% difference in the number of clicks. Such an increase in clicks on a CTA button is nothing to sneeze at for any business!

9 Essential A/B Testing Statistics

Businesses large and small are utilizing A/B testing, and the market is poised for growth.

  1. Business Insider predicts that the A/B testing software market will surpass $1.08 billion by 2025. (QY Research 2019)
  2. 51% of the top 10,000 sites on the internet were utilizing A/B testing as of October 2021,  (BuiltWith 2021)
  3. 27.1% of businesses using A/B tests are using client-side and server-side simultaneously, while 17.8% are running server side only. (CXL + Convert 2020)
  4. Using A/B testing, Hubspot determined that they could increase conversion rates by 50% on opt-in forms by reducing the number of form fields from 4 to 3. (Hubspot 2021)
  5. Hubspot used A/B testing in email subjects to increase their opening rate by 0.53%, which led to 131 new leads. (Hubspot 2021b)
  6. Csek Creative A/B tested two different layouts for their home pages, and increased total clicks by 8.2%.
  7. Only 1 in 8 of Appsumo A/B tests yielded results, but that result was a 500% increase in email conversion and a 200% increase in purchase conversion. (VWO Testing 2021)
  8. 57% of companies performing A/B testing are p-hacking, or stopping their tests once they reach a statistically significant p-score, indicating that they could generate false positives. (Berman, Pekele, Scott and Van den Bulte 2018)
  9. An A/B test on a website typically needs a sample size of 25,000 visitors to reach statistical significance. (VentureBeat, 2018)

A/B Testing News and Fundraising

Leanplum, but not Leanbudget 

Leanplum, who boasts big-name clients such as Tesco and TextNow, raised $27 million last year. The organization also appointed a new CEO, CFO, and CPO. Their platform allows for extensive A/B testing on websites and on mobile devices, allowing companies to test content, timing and which channel works best for various audiences.

Optimizely Proves A/B Testing is not Dead

Industry giant Optimizely acquired Zaius for an undisclosed amount in a deal announced in March 2021. Zaius is a customer data platform that when combined with Optimizely’s tools could allow for new and exciting A/B testing techniques using personalized customer data. Optimizely hopes that this wealth of additional customer data will help its own customers maximize their ROI since they discontinued the free version of their platform in 2018.

AB Tasty has an Appetite for Cash

French-based AB Tasty raised $40 in 2020 and is growing its market share outside of its home country. AB Tasty is capitalizing on the current trend towards personalization using A/B testing as an experienced tool, and it’s working. They’ve increased their US-based revenue by 480% over the past 2 years, and 60% of its business is now taking place outside of France. They plan to use the new investment in R&D efforts to increase their use of AI and automation.

Hottest A/B Testing Trends

Testing Based on Geography and Device 

Now that Apple has rolled out IDFA or identifier for advertisers it presents interesting opportunities for A/B testing. While advertisers have to ask for permission to track user data, they can use this data for new testing models that differ from more traditional tracking models based upon cookies. The potential for location-based A/B testing means that companies can use test results to tailor content to geographic locations.

Personalization Data

By personalizing testing, advertisers can deliver the most tailored experience to their users. A/B testing can be deployed using automation or machine learning to analyze browsing history. 

Beyond the geographic data gleaned from a user’s mobile device, testing and content can be personalized using browsing history and other demographic features that can be deduced using machine learning. 

Through experimenting with A/B testing with these specifics, companies can customize a person’s entire experience of their content, and hopefully increase their conversion and purchase rates along the way. This continued trend towards personalization may lead to A/B testing being used as an experienced tool in addition to a conversion rate optimization tool.

Companies Will Continue to Pay for CRO Services

By ensuring that they have the highest conversion rates possible, companies drive more traffic to their sites through ads and emails, and to more of their content online, while trying to minimize their bounce rate. 

This trend isn’t going to change because it increases income for businesses. As a vital part of the CRO toolkit, A/B testing isn’t going anywhere, despite predictions that it would when Optimizely discontinued its free offering. Instead, the A/B testing market share is projected to grow to a billion dollar industry by 2025, indicating that companies still see the value of A/B testing and are willing to pay for the insights and increases in profit that it brings.

If your organization is looking for A/B testing tools to get the most out of your content, it is vital to pick the right one for you. Click below to read real reviews and directly compare all A/B testing software.


  1. Global A/B Testing Software Market Size, Status and Forecast 2019-2025 (QY Research 2019)
  2. A/B Testing Usage Distribution in the Top 10k Sites (BuiltWith 2021)
  3. The 2020 State of Conversion Optimization Report (CXL + Convert 2020)
  4. Which Types of Form Fields Lower Landing Page Conversions? (Hubspot 2021a)
  5. How to Conduct the Perfect Marketing Experiment [+ Examples] (Hubspot 2021b)
  6. Two Great Examples of A/B Testing (Csek Creative 2021)
  7. Appsumo Reveals its A/B Testing Secret: Only 1 Out of 8 Tests Produce Results (VWO Testing 2021)
  8. p-Hacking and False Discovery in A/B Testing (Berman, Pekele, Scott and Van den Bulte 2018)
  9. Optimizely’s decision to ditch its free plan suggests A/B website testing is dead (VentureBeat, 2018)
  10. Optimizely Strengthens its Digital Experience Leadership with Acquisition of Customer Data Platform Zaius (Optimizely, 2021)

About the Author

Katie Allison
Katie leads the TrustRadius research team in their endeavors to ensure that technology buyers have the information they need to make confident purchase decisions. She and her team harness TrustRadius' data to create helpful content for technology buyers and vendors alike. Katie holds multiple degrees from the George Washington University with a BA in International Affairs and an MA in Forensic Psychology. When she’s not at work, you will either find her on an adventure with her two rescue dogs, or on the couch with a new book.

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