A command-line HTML pretty-printer: Making messy HTML readable [closed]

Question

I'm looking for recommendations for HTML pretty printers which fulfill the following requirements:

• Takes HTML as input, and then output a nicely formatted/correctly indented but "graphically equivalent" version of the given input HTML.
• Must support command-line operation.
• Must be open-source and run under Linux.

Holcombe

Other options are pup (without arguments), xmllint --format --html -, and xml fo --html. – Bourbon

curl httpbin.org | tidy -im – Leporine

Also: hxnormalize from html-xml-utils (Debian) – Platinum

related: #16091369 you can also look into XML Tools – Dissociation

I do have problems to get why this is considered off-topic, honestly... – Endocrinotherapy

Hey @VictorSchröder I think this is one of the few closed questions that are closed because of genuine non-compliance with the topic rules. I don't agree with the topic rules. I think recommendations of tools should be a core component, as none of want to "reinvent the wheel", at least not every day, for everything, so recommendations of good tooling is core to busines, but given they have that clause, this post doesn't comply. There are plenty of questions that are closed for far more ridiculous interpretations, unfortunately. It does seem to be a disease amongst SO admins. :-( – Asbury

Answer 1

Have a look at the HTML Tidy Project: http://www.html-tidy.org/

The granddaddy of HTML tools, with support for modern standards.

There used to be a fork called tidy-html5 which since became the official thing. Here is its GitHub repository.

Tidy is a console application for Mac OS X, Linux, Windows, UNIX, and more. It corrects and cleans up HTML and XML documents by fixing markup errors and upgrading legacy code to modern standards.

For your needs, here is the command line to call Tidy:

tidy inputfile.html

Flowerage

Thanks! "tidy -i -m -w 160 -ashtml -utf8 index.html" did the trick! Turns out tidy is installed by default in MacOS X - excellent! – Holcombe

Tidy was struggling with getting the indentation until I ran it with this option (rather than letting it default to "auto" with -i: tidy --indent yes – Arhat

Tidy is great as a validator/lint tool, but it's not so great as a code beautifier. Two issues: (1) it can only operate on files, not standard input (so you cannot, for example, send selected text from Notepad++ to tidy.exe, and have it output the formatted code back to Notepad++); (2) It has trouble formatting a lot of code, e.g.: <form><input><input><input><input><input></form>. – Amar

Also it modifies the file when it cannot understand text. – Circumvent

One note about tidy-html5, if you're using inline javascript, you need to include type="text/javascript" otherwise tidy will add <![CDATA[ – Achelous

tidy index.html -qi -utf8 --output index.html just a command done all things. – Topography

Tidy does more than just format the HTML. It will remove empty tags and reorder technically invalid HTML that is accept by browsers (read: is used on the internet). <p class="a"><div class="b"></div></p> gets reordered as <p class="a"></p><div class="b"></div> and something like <p><div></div></p> just gets deleted. See this GitHub issue. If you use tidy, you should run it in quiet mode tidy -q and don't ignore any warnings like trimming empty <p>. Don't use it on HTML you didn't write. – Allover

@Amar my version of tidy on Linux uses stdin, stdout and stderr if these are not specified in the options. I presume you are limited by your OS. – Asbury

Answer 2

Update 2018: The homebrew/dupes is now deprecated, tidy-html5 may be directly installed.

brew install tidy-html5

---

Original reply:

Tidy from OS X doesn't support HTML5. But there is experimental branch on Github which does.

To get it:

brew tap homebrew/dupes
brew install tidy --HEAD
brew untap homebrew/dupes

That's it! Have fun!

Classmate

Error: No available formula with the name "tidy". brew install tidy-html5 works. – Jacks

Indeed brew install tidy-html5 works and you don't neeed the homebrew/dupes tap either. – Seychelles

Tidy does more than just format the HTML. It will remove empty tags and reorder technically invalid HTML that is accept by browsers (read: is used on the internet). <p class="a"><div class="b"></div></p> gets reordered as <p class="a"></p><div class="b"></div> and something like <p><div></div></p> just gets deleted. See this GitHub issue. If you use tidy, you should run it in quiet mode tidy -q and don't ignore any warnings like trimming empty <p>. Don't use it on HTML you didn't write. – Allover

Answer 3

I think HTML tidy is one of the household names in that field.

Kinglet

Answer 4

To have an updated, OS-agnostic answer to this question:

While the original HTMLTidy project has been dormant for over 6 years, a "W3C Community & Business group" that goes by the name "HTML Tidy Advocacy Community Group (HTACG)" has now begun to continue its development, with the goal of making it fully HTML5-compatible. The group was formed in January 2015 and although they describe the current state as "work in progress", binaries are already available for download.

• Project homepage: http://www.html-tidy.org/
• Binary downloads: http://binaries.html-tidy.org/
• Github repository: https://github.com/htacg/tidy-html5
• Group page at W3C: https://www.w3.org/community/htacg/

Consist

Answer 5

Just a late followup on an OT question.

Homebrew has a tidy-html5 installed as you'd expect.

It's linked up as tidy5.

Cheryllches

Tidy still mostly as HTML formatter & validator, not HTML parser. Which tool can be used for HTML parsing based on rules: search the code for target elements (tags) with specified 'class' or 'id', and delete them, along with content (child tags)? Plus delete specified tags. – Magnetohydrodynamics

@triwo If you have a new question, particularly when not related to the original question, post a new question :) The caveat is that requests for tools/libraries/etc. are generally considered off-topic. In general, any HTML parser w/ XPath or CSS selector queries should be able to manipulate a DOM in arbitrary ways. – Cheryllches