Website optimization is the process of testing various elements of a page to see how people react to it. Your goal is to create a page that converts as many visitors as possible. The conversion could be many things, like newsletter sign ups, opt-ins, request for info, or a direct sale. When the test shows a clear winner (best content), you update your website with that particular version.

However, often people are not testing as much as they would like or should because they are afraid it negatively impacts Google and Bing search results. How? Well, for example: if you create different URL’s for basically the same page with just a different image or call to action (the element that’s being tested) then you could get into trouble due to duplicate content issues, or your test being perceived as cloaking (presenting different content to search engines than to users). Today we’ll discuss some best-practices so you can test all you want without having to worry about Google penalties!

Types of Tests

There are basically 2 types of tests that you can run:

1. A/B Tests: when you perform a test by creating multiple versions of a page, each with its own URL. When visitors try to access the original URL, some will be redirected to each of the variation URLs. You will then compare users’ behaviour to see which page is most effective.
2. Multivariate Tests: using software to change differents parts of your website on the fly. You can test changes to multiple parts of a page—for example, the heading, an image, and the ‘Add to Cart’ button—and the software will show variations of each of these parts to visitors in different combinations and then statistically analyze which variations are most effective. In this scenario, only 1 URL is involved; the variations are inserted dynamically on the page.

Do’s & Dont’s In Website Split Testing

Ok so how do these tests affect what search engine spiders (the software programs that crawl the web and read the content of web pages) see on your site?

Below advice comes from Google’s Webmaster Central and provides great tips on how to safely run tests with minimal impact on your website’s search rankings:

• No cloaking. Cloaking—showing one set of content to humans, and a different set to Googlebot—is against our Webmaster Guidelines, whether you’re running a test or not. Make sure that you’re not deciding whether to serve the test, or which content variant to serve, based on user-agent. An example of this would be always serving the original content when you see the user-agent “Googlebot.” Remember that infringing our Guidelines can get your site demoted or removed from Google search results—probably not the desired outcome of your test.

• Use rel=“canonical”. If you’re running an A/B test with multiple URLs, you can use the rel=“canonical” link attribute on all of your alternate URLs to indicate that the original URL is the preferred version. We recommend using rel=“canonical” rather than a noindex meta tag because it more closely matches your intent in this situation. Let’s say you were testing variations of your homepage; you don’t want search engines to not index your homepage, you just want them to understand that all the test URLs are close duplicates or variations on the original URL and should be grouped as such, with the original URL as the canonical. Using noindex rather than rel=“canonical” in such a situation can sometimes have unexpected effects (e.g., if for some reason we choose one of the variant URLs as the canonical, the “original” URL might also get dropped from the index since it would get treated as a duplicate).

• Use 302s, not 301s. If you’re running an A/B test that redirects users from the original URL to a variation URL, use a 302 (temporary) redirect, not a 301 (permanent) redirect. This tells search engines that this redirect is temporary—it will only be in place as long as you’re running the experiment—and that they should keep the original URL in their index rather than replacing it with the target of the redirect (the test page). JavaScript-based redirects are also fine.

• Only run the experiment as long as necessary. The amount of time required for a reliable test will vary depending on factors like your conversion rates, and how much traffic your website gets; a good testing tool should tell you when you’ve gathered enough data to draw a reliable conclusion. Once you’ve concluded the test, you should update your site with the desired content variation(s) and remove all elements of the test as soon as possible, such as alternate URLs or testing scripts and markup. If we discover a site running an experiment for an unnecessarily long time, we may interpret this as an attempt to deceive search engines and take action accordingly. This is especially true if you’re serving one content variant to a large percentage of your users.

The Right Tools For The Job

Hopefully you feel more comfortable now and you can start some split-tests on your own. There are various tools out there that do this job well. A free tool would be Google’s own Content Experiments within Google Analytics. Learn more by watching below video:

Another popular, but paid tool would be Visual Website Optimizer.

Check out these tools and others (just search for “website split testing tool”) and start testing. You know, improving the conversion rate of your website, even by 1 or 2% can mean a significant increase in sales or other business goals that you deem valuable!