Websites should be thoroughly tested for the following:

  1. Functionality
  2. Browser Consistency
  3. Performance

Testing Functionality

Functionality should be independent of the device, browser, or operating system that a visitor is using to view your website. Key functions should have been defined in the project specifications. Examples include:

  1. Being able to load all pages
  2. Ability to add products to a shopping cart and check out

Browser Consistency

There are hundreds of different versions of desktop and mobile web browsers. Luckily, almost all of them are based on one of four browser engines to render the page. It's very similar to how car manufacturers use the same engine/platform for different models of sedans or SUVs, or how video game companies will use the same graphics engines for their 3D games. That leaves us with only 4 desktop browsers and 2 mobile browsers we have to worry about:

Major desktop browsers

  1. Internet Explorer (version 9 and newer)
  2. Google Chrome
  3. Mozilla Firefox
  4. Apple Safari

Major Mobile Browsers

  1. Mobile Safari (all iOS devices)
  2. Chrome for Android

Mobile browsers will render a page very similarly to their desktop counterparts (Chrome for mobile vs Chrome for desktop) since they share the same browser engine.


Page load times are critical to the success of a website. Visitor frustration is directly related to how long they have to wait to access a page. Web page load times should be kept to a minimum. 1-2 seconds is a reasonable goal across a typical residential or commercial internet connection. Under 1 second is preferred.