Improving your website with Nibbler
If you haven’t encountered Nibbler before, Nibbler is a free-to-use website quality checker. It’s developed and maintained by Silktide, and is a tool for checking up to 5 pages of a website against 20 different quality checks - from Social Media to W3C compliance, Alternative text to Semantic HTML.
You can test any website - be it your own or a competitors’ website, and you’ll get the results from of a wide range of tests returned to you with both a grade, from 0.0 to a perfect 10, along with some background information and suggestions for improvement. Pretty neat, eh?