Website Speed: Onload Time vs Fully Loaded Time

Recently, website speed has become a major contributing factor in mobile search rankings. After Google announced the ‘Speed Update’ in July 2018, business website owners have taken more and more interest in just how fast their website loads, and what they can do to optimise speed.

Each month, clients who are on our Cheshire Web Agency ‘Premium’ subscription package, will receive a monthly speed report, highlighting how their WordPress website is performing, whilst other customers will use GT Metrix, Pingdom and several other third-party online speed testing tools to evaluate their website.

However, if you have used any of these speed testing tools, you may wonder why the results are inconsistent. The purpose of this blog is to help explain the key differences in website speed testing so our Cheshire web design customers have a better understanding.

What is Onload Time?

Onload Time is usually integrated with online speed testing tools such as Pingdom. Overload Time calculates the speed when the processing of the page is complete and all the resources on that particular page, such as images, CSS and other functionality have finished downloading. Once complete, the page will then trigger window.onload to complete the speed results.

However, one major flaw found with Onload Time is some elements of the page load may not make it in time before the trigger event is fired, such as Javascript files, images carousels, or functionality/content is set to a time delay, so it loads in a particular order. These variables will cause inconsistent page load times and may even falsely report your website to be faster/slower than it actually is.

What is Fully Loaded Time?

GT Metrix and Manage WP both use the Fully Loaded Time approach. Taking what we have learnt about ‘Onload Time, ‘Fully Loaded Time’ adopts the exact same process to record page speed but will add an additional two seconds after the ‘Onload’ trigger has fired to make sure there is no further network activity. The reasoning behind this is to ensure more consistently with tests.

One possible issue with Fully Loaded Time testing is this event fires only when a page completely stops loading content, including ads and other functionality. So, if your website has loaded before the cut-off point and still useable, the testing tool will still wait for the entire site to stop loading data, which again could lead to inconsistent speed testing results.

 

GT Metrix Manage WP Pingdom
Vancouver, Canada Vancouver, Canada Melbourne, Australia
Dallas, USA Dallas, USA San Jose, California
São Paulo, Brazil São Paulo, Brazil Stockholm, Sweden
London, UK London, UK New York, New York
Hong Kong, China Hong Kong, China
Mumbai, India Mumbai, India
Sydney, Australia Sydney, Australia

Different locations, different results

Where you test from will affect your performance results. It doesn’t matter if you choose to use GT Metrix, Pingdom or our WordPress website care package reports, each of these testing tools all offer multiple speed testing locations for analysis, in order to best represent your website performance score.

Naturally, the test location closest to your target audience will provide the most accurate data of your overall page load, as visitors will likely experience the same results from a geolocation point of view. So as a Cheshire web design agency, we would always choose London as our testing ground. For larger scale businesses, who may perhaps have an audience in Europe, results from other locations may vary due to network connection quality and/or third-party resources for ads.

A professional Cheshire Web Agency opinion

GT Metrix, Manage WP, Pingdom and other speed testing tools such as PageSpeed Insights all provide page speed analysis, however it’s critical to understand that each use their own metrics and testing practices to calculates results. As a professional web design agency, we highly advise that you understand how each tool works before being influenced to make any further decisions or question any inconsistences if you use multiple tools.

If you currently have a website care package with untitled™ and want to receive a page speed report, please do not hesitate to get in touch. If your website is supported elsewhere, we would still be more than happy to consult on how you could improve your website page speed.