20 January 2010 | Author: M. Thomson SEO & Affiliate Consultant

Preloading components using A/B testing to reduce page load times

If you are planning on changing your website's design or structure, you will likely have to go through some sort of migration. Post-migration, it is always useful to determine how effective your users find your new design. This can be achieved by A/B testing, which can be carried out using Google's Website Optimiser tool.

A/B testing can be used to compare the conversion rates of your new and existing websites. Once you have tested and concluded your findings, you can then safely say that your new design is worth implementing. But this is not the only benefit of A/B testing.

Page Load Times

When you do decide to migrate your old website to its new version, users will initially experience increased page load times due to the fact their browser has to cache all the components that make up your new website. When we refer to components, bigmouthmedia means CSS (cascading style sheets), JavaScript, images etc.

As all of these components are new, the user's browser will take longer to download and present the website in comparison to the old version, where they were likely cached. This will impact on how fast the new website loads - a key metric that users will respond to when critiquing your new website.

Introducing Preloading

Preloading is a technique that is used to load components that make up other webpages when the user's browser is idle, such as a page they are viewing that has fully loaded. Preloading can be broken down into three types:

Unconditional - immediately loads a set list of other components

Conditional - loads components based on anticipated user journeys

Anticipated - loads other components that you know will be required.

If you apply your use of A/B testing and your knowledge that page load times will be increased after a migration, you can see how preloading can be used to compliment part of your A/B testing strategy.

For example, while testing new designs, functionality and layouts, consider preloading components that you know your new website will use. When you do finally decide to migrate over to your new website, your action of preloading components during your A/B testing phase will make the new page load times much faster for users, as they will already have some of the components cached by their browser.

This strategic approach allows webmasters to kill two birds with one stone, and will likely help you to score highly when trying to justify the cost of introducing A/B testing.