How to check the quality of a website

This page is a short extract from our article “Website quality” and from several other pages where we set out what to look at when judging a site, and why.

Here we give only the essential links — the most dependable services for checking a site.

Checking speed

• Google PageSpeed Insights
• WebPagetest
• GTmetrix
• Pingdom Website speed test
• Uptrends Website Speed Test

Checking how it behaves on a phone

• Google Mobile-Friendly Test
• Google’s mobile site testing tool

Checking standards compliance

• HTML, CSS and links together
  • HTML validator
  • CSS validator
  • Link checker
• Internationalisation checker (whether the encoding and language of the site are declared correctly)