Multivariate vs A/B Testing: Difference Explained
Trustmary teamLast edited: September 27th, 2024
Here for a quick answer about the ultimate difference between A/B testing and multivariate testing?
I’ll give you the answer right away:
- A/B testing is testing between two versions of your page (usually)
- Multivariate testing is testing multiple variables and their combinations
If that did not quite satisfy your hunger for information, no worries. I have a more thorough comparison below.
A/B Testing Explained
A/B testing is a conversion rate optimization strategy where you aim to find out which of the two versions of your website performs better = converts more.
Generally, an A/B test includes two versions of your website or a website element. These versions should have only one difference in order for us to see how this one factor affects conversion rates.
In practice, this means that you have your original website, create another version of it with a small change, and ask yourself the question: does the new version perform better than the current version?
Use case could be
- Which image works best
- Which CTA button placement works best
- Which review works best
- And other details like that
If you start an A/B test with too many page elements, you cannot be sure which of them affected the results of the experiment. The methodology just isn’t flexible enough for that.
Multivariate Testing Definition
Multivariate testing (MVT testing) is A/B testing on steroids.
Instead of two variables, you can examine different page elements and their combinations!
For example, you can take three different images and three different fonts, and create a separate page version for each combination, resulting in 9 different versions of the page.
With this method, you will learn how the variables interact with each other: aka which elements work best together.
However, don’t go too crazy, as otherwise the test will become too heavy and take too much time.
In fact, multivariate tests are quite complex and take time to complete, which is why you should focus on the bigger picture.
Choose elements that truly make a difference for your conversion rate, rather than fixing smaller details (leave that for the A/B testers).
Use cases for multivariate testing:
- When you want to make radical changes
- Seeing how different elements work together
- When you have several improvement ideas and want to test all of them at the same time
What’s the difference between the two?
Technically, multivariate testing is a “subcategory” of A/B testing.
Once more: The difference is that while A/B tests usually focus on one variable at a time, multivariate testing (much like the name suggests) can be used to test multiple variables at the same time.
Attention! The example image below features 9 different versions of a website, but that doesn’t mean it must be exactly the same for your test.
Take a look at the table for a more detailed comparison.
| A/B | MVT |
| Test two variables of one element | Test combinations of multiple variables of multiple elements |
| Good for testing details | Good for larger radical changes |
| Tells you which version is better | Tells you which combination of elements is the best |
| Can be used for websites that have less traffic | Requires a lot of traffic to be divided into multiple samples. |
| Results are easy to interpret | Analyzing results can be difficult |
| Results are clear and specific | Results can be ambiguous and test can fail to produce meaningful results |
| Quick to set up and run | Is relatively difficult to set up and takes longer to complete |
| Relatively simple methodology | Complex methodology |
| Suitable for beginners | Better for advanced optimizers |
Similarities between the two
Now, let’s see what these two have in common!
The similarities have to do more with the planning process, how to get the best results, and how to react to them.
- Before starting a test, analyze your issue
- Determine a conversion goal
- Form a hypothesis or multiple hypotheses
- Carefully set up the test so that it measures what you want it to measure
- Drive enough traffic to each test page
- Results need to be statistically significant in order to be meaningful
- After analyzing results and confirming that they are accurate, implement changes
- Both tests can be run with the help of software tools
- Successful tests will help you get more conversions and sales
- If you notice no significant change in test results, you should turn your attention to other things than your website.
How about using them simultaneously?
As you can see, both testing methods have their own advantages and disadvantages. You might be wondering if you could leverage both of them at the same time.
It is not recommended to run multiple tests at the same time for the same page. It is extremely difficult to divide the traffic evenly between all different versions of the page, and it would take a long time to reach statistical significance.
However, using one or the other doesn’t mean you have to stick with it forever!
If you have multiple landing pages, you can test one landing page with MVT test and another with A/B test if that would speed up the process of figuring out how to organize your website in the long run. This strategy has its dangers, though.
It might be a good idea to use the methods as supporting each other in the conversion optimization process.
For example, if you have two very very different landing page ideas (to the extent that you are not even talking about the same elements) you could run an A/B test with the two pages first, find out the best performing page, and then dig deeper into which individual elements and combinations maximize the effect.
Just keep in mind that running these tests is away from your other tasks, and you should carefully evaluate whether the tests are the best way to spend your time and effort.
What to do if there is no improvement?
A/B and multivariate testing are effective conversion rate optimization techniques that can help you get most out of your existing website traffic.
Just remember that website conversion optimization is not everything. If the tests show no significant improvement in conversion rate whatever you do, it is not a sign that you should run more tests: it’s a sign that you should focus on improving something else.
Maybe you need more traffic in the first place (do more outreach marketing), or it is something about your product, price, customer experience, credibility, and so on.
To find out what is really preventing your website visitors from converting, conduct feedback surveys and ask the visitors directly!
A/B vs. Multivariate Testing
The difference between A/B and multivariate testing is that
- in A/B testing you test between two versions of your web page (without knowing what actually causes the differences in conversions), and
- multivariate test takes into account all the elements and all the possible combinations, revealing which exact page elements visitors interact the most with.
Both testing methods have their pros and cons, and you should carefully consider which one is better for your next test.
It is possible to use both tests as supporting each other in your optimization process, but not at the exact same time.
Don’t forget to evaluate whether website conversion optimization is the best thing you can do for your business right now. If you don’t have a lot of traffic already, or if your product is lacking, there are more pressing issues to solve.
If you have traffic, doubling down on CRO marketing might be a winning strategy.
When you decide to run a multivariate or A/B test, there are plenty of software tools to help you, like Trustmary.
Further Reading
FAQ
What is the difference between A/B testing and multivariate testing?
The difference between the two methods is that an A/B test can tell you which of the (usually two) versions of the page perform better, and multivariate (MVT) test can tell you which out of all possible combinations of page elements result in most conversions.
What similarities are there between A/B and multivariate tests?
Both testing methods require you to carefully analyze your issue, set goals, form hypotheses, ensure enough traffic to the tested pages, and in the best case, both help you get more conversions from your website and grow your business.
Can I use A/B and multivariate testing at the same time?
It is not recommended to run multiple tests at the same time, as it can interfere with the result and take a long time to complete. However, you can use both methods in your CRO efforts on different pages and at a different time.
What does it mean if A/B or MVT test shows no significant difference?
In case your successful tests and well-analyzed results show no difference in conversions between the websites, it means that both websites perform as well (or bad). Either you have such an attractive product that the website planning has no effect on the willingness to convert, or something prevents visitors from converting. I recommend you conduct feedback surveys to find out what your visitors and customers think.
