Website Front End Performance Testing Series - Part 3 - What is Front End Performance Test?

In the Part 2 of Website Front End Performance Testing Series, we identified, what is the front end of a website. This part of WFEPT Series is dedicated to learn what is front end performance test and how it differs from load tests.

Few years back, when we talked about website performance optimization, we meant optimizing its server-side only since web sites were mostly static and almost all the processing was done on server side. But, the arrival of modern web technologies like Javascript, AJAX and CSS has put lots of emphasis on "Application like" interactions of web applications which puts more and more complexity on the front end rather than backend.

Because of that, today, bad user experiences not only occur due to application, database, servers and infrastructures tuning but also due to the time it takes to load the web page and displaying its contents on end-user screen. This modern web applications architecture has forced the Performance Engineers to rethink about the performance testing and optimization strategies.



Difference between Frontend performance testing and Load testing ?

Load testing / Backend Performance Testing is about "How fast does this page load when 1000 concurrent users are working on the application?" that is from a multiple users point of view where resources are used concurrently. Front-end Performance testing is about "How fast does this page is rendered inside a browser, from a single user point of view".

What are being tested in Frontend Performance Test?

In Frontend Performance Testing, we focus on identifying quality defects related to frontends of websites. These defects can mainly related to frontend technologies like Javascript, CSS, network utilization, cache or payload. Above quality defects in websites would result in bad user experience for end-users.