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When I'm developing a website locally sometimes I want to check if the html is valid but I haven't been able to find a good tool. I want it partial as a sanity check when I'm troubleshooting layout issues.
Can you please suggest a tool that can validate HTML offline? I'm not looking for validation inside of an IDE but something that will load the page from the web server.
Thank you!
You can download the source and/or packages direct from w3[1].
To save time I use a Firefox Extension called HTML Validator. It adds validation to your view source window, tells you errors and warnings in a bottom pane. Also puts an icon in the bottom of your window showing you a quick reference for yes/no on validation. If no, then you just view source and it shows you exactly what your errors are.
Also validates accessibility.
Have you checked out HTML Tidy?
You can validate HTML and CSS locally (and do a lot of other useful things) with the Web Developer Toolbar add-on for Firefox. It's also available for Google Chrome.
In Debian/Ubuntu you can do:
sudo apt-get install w3c-markup-validator
This will get you the web interface.
If you want to validate from the console, edit /usr/share/doc/w3c-markup-validator/examples/validate.pl and install libwebservice-validator-html-w3c-perl. Now you can run validate.pl with an URL to validate.
validate.pl so it can be run from command line with local file? I don't know python and am not sure how to do it.
You can now use the new Linux command line tool htmlval for checking HTML and CSS. With the Linux version, you can use curl to download a URL and pipe it to htmlval.
It will work offline, but of course you need to be online if you're going to fetch a URL from the Internet.
There's also a Windows version of the program.
Note: I'm the developer.
Testing this HTML (in file example.html):
<!DOCTYPE HTML>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title></title>
</head>
<body>
<badtag>
<span>span has no end tag
</body>
</html>
With this command (-l for list format, -S for no SEO messages):
htmlval -lS example.html
Produces this error list:
=================================
=== File 1 of 1: example.html ===
=================================
Error (line 6, col 11): This document has a <title> element but it does not contain a title when it must. Each page on a site should have its own unique (never duplicated) and well-written title.
Error (line 9, col 2): The <badtag> element is not valid. Is it misspelled?
Error (line 10, col 2): The <span> element must have an end tag (</span>) but the end tag was not found, is misplaced, misspelled, or was not seen due to other errors.
Error (line 11, col 2): The end tag for <span> (started in line 10, column 2) should appear before this </body> end tag or this end tag should be deleted or moved. This is a nesting error.
Comment: "Errors and warnings only" mode enabled. Showing only error and warning messages (with some exceptions).
