Tidy HTML Validator
There are several HTML validation routines around. I happen to like this one beacuse it's not overly pedantic about tiny details, and it gives a neat concise explanation of the reasons why it thinks your HTML is incorrect.It comes as a Firefox extension, and puts a little green tick on the status bar when it considers your code to be valid, so you don't have to keep remembering to send your page to an external validator whenever you change something, you just watch to see if the green tick turns into a yellow triangle or a red cross.I don't think it's always 100% right, but I recommend it for the neatness and convenience.The Windows version is here. There are Linux, MacOSX and FreeBSD versions here.
Blogged with Flock