Sweeping Away your Poor HTML Clutter since 2002!

Use Balthisar Tidy to make sure your HTML is clean, error free, accessible, and valid. With full support for modern HTML5, Tidy HTML, and the W3C Nu Validator, Balthisar Tidy surpasses macOS's built-in, terminal version of this venerable tool.

Balthisar Tidy gives you all of these features absolutely free:

• Tidy and check your documents with HTML Tidy.
• Validate your document conformance with the W3C Nu HTML Checker using the built-in checker or with the official validator service.
• Balthisar Tidy can tidy documents in other applications as a Service.
• Balthisar Tidy can tidy documents in other applications as an Action Extension.
• Full-featured text editor with instant results.
• Supports every macOS file encoding.
• See a live preview of the effects each Tidy option has on your code.
• See a live Browser Preview of the Tidy’d code.
• Identify errors and be directed to their exact location in your source code in an instant.
• Correct errors in the source document immediately.
• Identifies and automatically corrects several potential errors.
• Automatically cleans up ugly code from HTML generator applications.
• Identifies opportunities to ensure accessibility compliance.
• Pretty-print formats your source code for maximum legibility.

There are no options for in-app purchases, no nag screens, and no annoying advertisements.

What’s New

Version 4.1.0

• Full support for Dark Mode on macOS 10.14 and above.
• Updated the built-in W3C Nu HTML Checker

Ratings and Reviews

5.0 out of 5
1 Rating

1 Rating

Arinitti ,

A great tool for any web designer or developer.

Clean code makes all the difference!

mwpdx ,

Nice GUI utility for tidy; could use some minor tweaks

This is a GUI app wrapping the classic tidy utility, very helpful if you’d like to bypass fiddling with command line issues for quick experimentation. A drawback that will hinder some is that it appears to enforce an html file extension, so won’t open xml or other files. It would be useful to have the ability to hide the options and messages panes to maximize screen real estate for input/output review. Also, it would benefit keyboard-centric users to have keyboard shortcuts to set options, eg the pane show/hide functionality, toggling tidy settings, etc. Other than these minor issues, it’s a worthy repackaging of the great tidy functionality.

Bucky Junior ,

This program made undesired changes to my system icons

After a spirited discussion on the BBEdit forum, I installed this to see what the talk was about. I opened two files, one an HTML file and the other a PHP file. My very first impression was that it gave a warning about being a 4.1 Transitional Doctype. A warning? Really. It was written that way on purpose. Then it said there was no <title></title> when there was.

Nothing was altered, nothing was saved from Balthisar Tidy.

After returning to BBEdit to get some work done, I found that all of my PHP files’ icons had been changed to Balthisar Tidy icons. NOT what I requested. I was NOT asked, the program changed a system wide setting without my approval. I am not a happy camper. This one goes in my trash.


James Derry
78.3 MB
Developer Tools

OS X 10.10 or later, 64-bit processor



Age Rating
Rated 4+
©2018 Jim Derry and


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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