Clean up your Web pageswith HTML TIDY
Clean up your Web pagesThis version 22nd October 1999
Copyright © 1999 W3C, see tidy.c for copyright notice.
With many thanks to Hewlett Packard for financial support during the development of this software!
How to use Tidy | Downloading Tidy |
Release Notes
Integration with other Software | Acknowledgements
To get the latest version of Tidy please visit the original version of this page at: http://www.w3.org/People/Raggett/tidy/. Courtesy of Netmind, you can register for email reminders when new versions of tidy become available.
The public email list devoted to HTML Tidy is: <html-tidy@w3.org>. To subscribe send an email to html-tidy-request@w3.org with the word subscribe in the subject line (include the word unsubscribe if you want to unsubscribe). The archive for this list is accessible online. Please use this list to report errors or enhancement requests. See the release notes for information on recent changes. Your feedback is welcome!
If you find HTML Tidy useful and you would like to say thanks, then please send me a (paper) postcard or other souvenir from the area in which you live along with a few words on what you are using Tidy for. It will be fun to map out where Tidy users are to be found! My postal address is given at the end of this file.
Tidy can now perform wonders on HTML saved from Microsoft Word 2000! Word bulks out HTML files with stuff for round-tripping presentation between HTML and Word. If you are more concerned about using HTML on the Web, check out Tidy's new "Word'2000" config option! Of course Tidy does a good job on Word'97 files as well!
When editing HTML it's easy to make mistakes. Wouldn't it be nice if there was a simple way to fix these mistakes automatically and tidy up sloppy editing into nicely layed out markup? Well now there is! Dave Raggett's HTML TIDY is a free utility for doing just that. It also works great on the atrociously hard to read markup generated by specialized HTML editors and conversion tools, and can help you identify where you need to pay further attention on making your pages more accessible to people with disabilities.
Tidy is able to fix up a wide range of problems and to bring to your attention things that you need to work on yourself. Each item found is listed with the line number and column so that you can see where the problem lies in your markup. Tidy won't generate a cleaned up version when there are problems that it can't be sure of how to handle. These are logged as "errors" rather than "warnings".
Tidy features in a recent article on XHTML by webreview.com.
Tidy corrects the markup in a way that matches where possible the observed rendering in popular browsers from Netscape and Microsoft. Here are just a few examples of how TIDY perfects your HTML for you:
<h1>heading <h2>subheading</h3>
is mapped to
<h1>heading</h1> <h2>subheading</h2>
<p>here is a para <b>bold <i>bold italic</b> bold?</i> normal?
is mapped to
<p>here is a para <b>bold <i>bold italic</i> bold?</b> normal?
<h1><i>italic heading</h1> <p>new paragraph
In Netscape and Internet Explorer this causes everything following the heading to be in the heading font size, not the desired effect at all!
Tidy maps the example to
<h1><i>italic heading</i></h1> <p>new paragraph
<i><h1>heading</h1></i> <p>new paragraph <b>bold text <p>some more bold text
Tidy maps this to
<h1><i>heading</i></h1> <p>new paragraph <b>bold text</b> <p><b>some more bold text</b>
<h1><hr>heading</h1> <h2>sub<hr>heading</h2>
Tidy maps this to
<hr> <h1>heading</h1> <h2>sub</h2> <hr> <h2>heading</h2>
<a href="#refs">References<a>
Tidy maps this to
<a href="#refs">References</a>
<body> <li>1st list item <li>2nd list item
is mapped to
<body> <ul> <li>1st list item</li> <li>2nd list item</li> </ul>
Tidy inserts quote marks around all attribute values for you. It can also detect when you have forgotten the closing quote mark, although this is something you will have to fix yourself.
Tidy has a comprehensive knowledge of the attributes defined in the HTML 4.0 recommendation from W3C. This often allows you to spot where you have mistyped an attribute or value.
Tidy will even work out which version of HTML you are using and insert the appropriate DOCTYPE element, as per the W3C recommendations.
This is something you then have to fix yourself as Tidy is unsure of where the > should be inserted.
You can choose which style you want Tidy to use when it generates the cleaned up markup: for instance whether you like elements to indent their contents or not. Several people have asked if Tidy could preserve the original layout. I am sorry to say that this would be very hard to support due to the way Tidy is implemented. Tidy starts by building a clean parse tree from the source file. The parse tree doesn't contain any information about the original layout. Tidy then pretty prints the parse tree using the current layout options. Trying to preserve the original layout would interact badly with the repair operations needed to build a clean parse tree and considerably complicate the code.
Some browsers can screw up the right alignment of text depending on how you layout headings. As an example, consider:
<h1 align="right"> Heading </h1> <h1 align="right">Heading</h1>
Both of these should be rendered the same. Sadly a common browser bug fails to trim trailing whitespace and misaligns the first heading. HTML Tidy will protect you from this bug, except when you set the indent option to "yes".
Setting the indent option to yes can also cause problems with table layout for some browsers:
<td><img src="foo.gif"></td> <td><img src="foo.gif"></td>
will look slightly different from:
<td> <img src="foo.gif"> </td> <td> <img src="foo.gif"> </td>
You can avoid such quirks by using indent: no or indent: auto in the config file.
Tidy offers you a choice of character encodings: US ASCII, ISO Latin-1, UTF-8 and the ISO 2022 family of 7 bit encodings. The full set of HTML 4.0 entities are defined. Cleaned up output uses HTML entity names for characters when appropriate. Otherwise characters outside the normal range are output as numeric character entities. Tidy defaults to assuming you want the output to be in US ASCII. Tidy doesn't yet recognize the use of the HTML meta element for specifying the character encoding.
Tidy offers advice on accessibility problems for people using non-graphical browsers. The most common thing you will see is the suggestion you add a summary attribute to table elements. The idea is to provide a summary of the table's role and structure suitable for use with aural browsers.
Many tools generate HTML with an excess of FONT, NOBR and CENTER tags. Tidy's -clean option will replace them by style properties and rules using CSS. This makes the markup easier to read and maintain as well as reducing the file size! Tidy is expected to get smarter at this in the future.
Some pages rely on the presentation effects of isolated <p> or </p> tags.Tidy deletes empty paragraph and heading elements etc. The use of empty paragraph elements is not recommended for adding vertical whitespace. Instead use style sheets, or the <br> element. Tidy won't discard paragraphs only containing a nonbreaking space
You can teach Tidy about new tags by declaring them in the configuration file, the syntax is:
new-inline-tags: tag1, tag2, tag3 new-empty-tags: tag1, tag2, tag3 new-blocklevel-tags: tag1, tag2, tag3 new-pre-tags: tag1, tag2, tag3
The same tag can be defined as empty and as inline or as empty and as block.
These declarations can be combined to define an a new empty inline or empty block element, but you are not advised to declare tags as being both inline and block!
Note that the new tags can only appear where Tidy expects inline or block-level tags respectively. This means you can't (yet) place new tags within the document head or other contexts with restricted content models. So far the most popular use of this feature is to allow Tidy to be applied to Cold Fusion files.
I am working on ways to make it easy to customize the permitted document syntax using assertion grammars, and hope to apply this to a much smarter version of Tidy for release later this year or early next year.
Tidy is somewhat aware of the preprocessing language called ASP which uses a pseudo element syntax <% ... %> to include preprocessor directives. ASP is normally interpreted by the web server before delivery to the browser. Tidy can also cope with another such language called PHP, which uses the syntax <?php ... ?>
Tidy will cope with ASP and PHP pseudo elements within element content and as replacements for attributes, for example:
<option <% if rsSchool.Fields("ID").Value
= session("sessSchoolID")
then Response.Write("selected") %>
value='<%=rsSchool.Fields("ID").Value%>'>
<%=rsSchool.Fields("Name").Value%>
(<%=rsSchool.Fields("ID").Value%>)
</option>
Note that Tidy doesn't understand the scripting language used within ASP, and can easily get confused. Tidy may report missing attributes when these are hidden within ASP code. Tidy can also get things wrong if the ASP code includes quote marks, e.g. if the example above is changed to:
value="<%=rsSchool.Fields("ID").Value%>"
Tidy will now see the quote mark preceding ID as ending the attribute value, and proceed to complain about what follows. Note you can choose whether to allow line wrapping on spaces within ASP pseudo elements or not using the wrap-asp option. If you used ASP or PHP to create a start tag, but placed the end tag explicitly in the markup, Tidy won't be able to match them up, and will delete the end tag for you. So in this case you are advise to make the start tag explicit and to use ASP or PHP for just the attributes, e.g.
<a href="<%=random.site()%>">do you feel lucky?</a>
Tidy allows you to control whether line wrapping is enabled for ASP and PHP instructions, see the wrap-asp and wrap-php config options, respectively.
I regret that Tidy does not support Tango preprocessing instructions which look like:
<@if variable_1='a'>
do something
<@else>
do nothing
</@if>
<@include <@cgi><@appfilepath>includes/message.html>
Adding support for Tango looks as if it will be quite tough, so I would like to gauge the level of interest before committing to this work. Note that you can use Tango for attribute values.
XML processors compliant with W3C's XML 1.0 recommendation are very picky about which files they will accept. Tidy can help you to fix errors that cause your XML files to be rejected. Tidy doesn't yet recognize all XML features though, e.g. it doesn't understand CDATA sections or DTD subsets.
The -slides option allows you to burst a single HTML file into a number of linked slides. Each H2 element in the input file is treated as delimiting the start of the next slide. The slides are named slide1.html, slide2.html, slide3.html etc. This is a relatively new feature and ideas are welcomed as to how to improve it. In particular, I plan to add support to the configuration file for setting the style sheet for slides and for customizing the slides via a template.
I would be interested in hearing from anyone who can offer help with using Javascript for adding dynamic effects to slides, for instance similar to those available in Microsoft PowerPoint.
Indenting the content of elements makes the markup easier to read. Tidy can do this for all elements or just for those where it's needed. The auto-indent mode has been used below to avoid indenting the content of title, p and li elements:
<html>
<head>
<title>Test document</title>
</head>
<body>
<p>para which has enough text to cause a line break,
and so test the wrapping mechanism for long lines.</p>
<pre>
This is
<em>genuine
preformatted</em>
text
</pre>
<ul>
<li>1st list item</li>
<li>2nd list item</li>
</ul>
<!-- end comment -->
</body>
</html>
Indenting the content does increase the size of the file, so you may prefer Tidy's default style:
<html>
<head>
<title>Test document</title>
</head>
<body>
<p>para which has enough text to cause a line break,
and so test the wrapping mechanism for long lines.</p>
<pre>This is
<em>genuine
preformatted</em>
text
</pre>
<ul>
<li>1st list item </li>
<li>2nd list item</li>
</ul>
<!-- end comment -->
</body>
</html>
tidy [[options] filename]*
HTML tidy is not (yet) a windows program. If you run tidy without any arguments, it will just sit there waiting to read markup on the stdin stream. Tidy's input and output default to stdin and stdout respectively. Errors are written to stderr but can be redirected to a file with the -f filename option.
I generally use the -m option to get tidy to update the original file, and if the file is particularly bad I also use the -f option to write the errors to a file to make it easier to review them. Tidy supports a small set of character encoding options. The default is ASCII, which makes it easy to edit markup in regular text editors.
For instance:
tidy -f errs.txt -m index.html
which runs tidy on the file "index.html" updating it in place and writing the error messages to the file "errs.txt". Its a good idea to save your work before tidying it, as with all complex software, tidy may have bugs. If you find any please let me know!
Users running in Microsoft Windows should be aware that Dos doesn't expand wild cards in filenames. This means that if you have several html files in the same directory and want to tidy all of them:
tidy *.html
won't work. You will see an error message: "can't open file *.html". Instead you need to run tidy separately on each one. I will look into a fix for this for a future release. A work around is to use the DOS for command, as in:
for %i in (*.html) do tidy %i
Note: in a batch file that needs to be %%i instead of %i
Tidy writes errors to stderr, and won't be paused by the more command. A work around is to redirect stderr to stdout as follows. This works on Unix and Windows NT, but not on other platforms. My thanks to Markus Wolf for this tip!
tidy file.html 2>&1 | more
To get a list of available options use:
tidy -help
You should see something like this:
options for tidy vers: 14th April 1999 -config file read config file -indent or -i indent element content -omit or -o omit optional endtags -wrap 72 wrap text at column 72 (default is 68) -upper or -u force tags to upper case (default is lower) -clean or -c replace font, nobr & center tags by CSS -raw don't o/p entities for chars 128 to 255 -ascii use ASCII for output, Latin-1 for input -latin1 use Latin-1 for both input and output -utf8 use UTF-8 for both input and output -iso2022 use ISO2022 for both input and output -numeric or -n output numeric rather than named entities -modify or -m to modify original files -errors or -e show only error messages -quiet or -q suppress non-essential output -f file write errors to file -xml use this when input is in XML -asxml to convert HTML to XML -slides to burst into slides on h2 elements -help list command line options
Input and Output default to stdin/stdout respectively. Single letter options apart from -f may be combined as in: tidy -f errs.txt -imu foo.html
Matej Vela <vela@debian.org> has written a Unix man page for Tidy, but for the latest details on config options and for the release notes please visit this page: http://www.w3.org/People/Raggett/tidy.
Tidy now supports a configuration file, and this is now much the most convenient way to configure Tidy. Assuming you have created a config file named "config.txt" (the name doesn't matter), you can instruct Tidy to use it via the command line option -config config.txt, e.g.
tidy -config config.txt file1.html file2.html
Alternatively, you can name the default config file via the environment variable named "HTML_TIDY". Note this should be the absolute path since you are likely to want to run Tidy in different directories. You can also set a config file at compile time by defining CONFIG_FILE as the path string, see platform.h.
You can now set config options on the command line by preceding the name of the option immediately (no intervening space) by "--", for example:
tidy --break-before-br true --show-warnings false
The following options are supported:
doctype: "-//ACME//DTD HTML 3.14159//EN"
<a href="somewhere.html" onmouseover="document.status = '...some \ really, really, really, really, really, really, really, really, \ really, really long string..';">test</a>
This is just an example to get you started.
// sample config file for HTML tidy indent: auto indent-spaces: 2 wrap: 72 markup: yes output-xml: no input-xml: no show-warnings: yes numeric-entities: yes quote-marks: yes quote-nbsp: yes quote-ampersand: no break-before-br: no uppercase-tags: no uppercase-attributes: no char-encoding: latin1 new-inline-tags: cfif, cfelse, math, mroot, mrow, mi, mn, mo, msqrt, mfrac, msubsup, munderover, munder, mover, mmultiscripts, msup, msub, mtext, mprescripts, mtable, mtr, mtd, mth new-blocklevel-tags: cfoutput, cfquery new-empty-tags: cfelse
If you want to run Tidy from a Perl or other scripting language you may find it of value to inspect the result returned by Tidy when it exits: 0 if everything is fine, 1 if there were warnings and 2 if there were errors. This is an example using Perl:
if (close(TIDY) == 0) {
my $exitcode = $? >> 8;
if ($exitcode == 1) {
printf STDERR "tidy issued warning messages\n";
} elsif ($exitcode == 2) {
printf STDERR "tidy issued error messages\n";
} else {
die "tidy exited with code: $exitcode\n";
}
} else {
printf STDERR "tidy detected no errors\n";
}
If you are prepared to maintain a public URL for HTML Tidy compiled for a specific platform, please let me know so that I can add a link to your page. This will avoid the need for me to update this page whenever you recompile.
Windows users! A free graphical user interface (HTML-Kit) for HTML Tidy is now available for windows 95/98/NT. Alternatively, you can get tidy in its native form as a Windows (win32) console program: tidy.exe, with the command options as per above. A version of Tidy for Windows 3.11 is in preparation.
Mac users! You can now run HTML Tidy as a standalone Macintosh application with a graphical user interface, or as a FilterTop filter (Screenshot). My thanks to Terry Teague for this port.
Amiga users! Keith Blakemore-Noble has compiled Tidy for the Amiga.
AIX executable for Tidy! Compiled by Ciaran Deignan. The link is to a general download page. The executable is available for AIX 4.3.2 and later.
Tidy RPM Package for Redhat Linux, maintained by Dimitri Papadopoulos. Tidy may also be available from other Linux distribution sites, e.g. http://rpmfind.net/, and http://www.fte.dk/~mbn/tidy/ which offers two versions one Danish, and one English, thanks to Morten Blinksbjerg Nielsen.
Tidy for UnixWare! Simon Trimmer is maintaining a Tidy binary for Unixware.
Tidy386 for DOS, maintained by Nick B. This exploits the DPMI mechanism for the memory management.
You can also incorporate Tidy as part of a larger program, for instance in HTML editors or HTML transformation tools used for import filters, or for when you want to customize Web content to get the best out of different kinds of browsers. Imagine authoring clean HTML with CSS and at a touch of a button producing variants that look great and work reliably on a large variety of different browsers, taking into account the quirks of each. For instance, providing the ability to tune content for different versions of Netscape and Internet Explorer, and for browsers running on set-top boxes for televisions, handheld and palmtop devices, cell phones, and voice browsers. I am happy to quote for software development for such tools.
Andy Quick has ported Tidy to Java, so that you can now integrate Tidy into your Java applications. More information is available on Andy's home page. Andy writes:
It uses some nice features of Java, such as resource bundles (for internationalization). The current state of the project is: I have ran a few simple tests, and it seems to work. In other words, it is beta software :-) I still have to implement the clean functionality (from clean.c) and do a lot more testing. I would be willing to bring the Java version to a stable version. After that, I may be interested in supporting it, but I could at least pass it on to somebody who is interested in supporting it.
The code is in ANSI C and uses the C standard library for i/o. The parser works top down, building a complete parse tree in memory. Document text is held as Unicode represented as UTF-8 in a character buffer that expands as needed. The code has so far been tested on Windows'95, Windows'98, Windows NT, Linux, FreeBSD, NetBSD, Ultrix, OSF, OS/MP, IRIX, NeXtStep, MacOS, BeOS, OS2, AIX, Amiga, SunOS, Solaris, IRIX and HP-UX, amongst others.
Conventions for whether lines end with CRLF, LF or CR vary from one system to another. I have included the C source for a utility tab2space which can be used to ensure that files use the line end convention of your choice, and to expand tabs to spaces.
tab2space -t4 -unix *.h *.c tab2space -tabs -unix Makefile
Note use of "-tabs" to ensure that tabs are preserved in the Makefile (it won't work without them!).
For those of you on Unix, here is a script you can use to strip carriage returns:
#!/bin/sh
echo Stripping Carriage Returns from files...
for i
do
# If a writable file
if [ -f $i ]
then
if [ -w $i ]
then
echo $i
# strip CRs from input and output to temp file
tr -d '\015' < $i > toix.tmp
mv toix.tmp $i
else
echo $i: write-protected
fi
else
echo $i: not a file
fi
done
Save this script to a file, e.g. "scripcr" and use "chmod +x stripcr" to make it executable. You can then run it as "stripcr *.c *.h Overview.html Makefile"
I would like to thank the many people who have written to me with suggestions for improvements or reporting bugs. Your help has been invaluable.
Drew Adams, Osma Ahvenlampi, Carsten Allefeld, Richard Allsebrook, Jacob Sparre Andersen, Joe D'Andrea, Jerry Andrews, Bruce Aron, Edward Avis, Nick B, Chang Hyun Baek, Nick B, Chuck Baslock, Christer Bernerus, Yu Jian Bin, Alexander Biron, Keith Blakemore-Noble, Eric Blossom, ochen M. Braun, David Brooke, Andy Brown, Keith B. Brown, Andreas Buchholz, Maurice Buxton, Jelks Cabaniss, Trevor Carden, Terry Cassidy, Mathew Cepl, Kendall Clark, Rob Clark, Jeremy Clulow, Dan Connolly, Larry Cousin, Ken Cox, John Cumming, Keith Davies, Ciaran Deignan, Tamminen Eero, Bodo Eing, Baruch Even, David Fallon, Claus André Färber, Stephanie Foott, Darren Forcier, Frederik Fouvry, Rene Fritz, Martin Gallwey, Francisco Guardiola, David Getchell, Michael Giroux, Guus Goos, Léa Gris, Juha Häikiö, Vlad Harchev, Shane Harrelson, Andre Hinrichs, Bjoern Hoehrmann, G. Ken Holman, Bill Homer, Craig Horman, Jack Horsfield, Pao-Hsi Huang, Marc Jauvin, Rick Jelliffe, Peter Jeremy, Craig Johnson, Charles LaFountain, Steven Lobo, Zdenek Kabelac, Michael Kay, Axel Kielhorn, Johannes Koch, Rudy Kohut, Allan Kuchinsky, Volker Kuhlmann, Michael LaStella, Steve Lee, Tony Leneis, Nick Leverton, Todd Lewis, Dietmar Lippold, Gert-Jan C. Lokhorst, John Love-Jensen, Satwinder Mangat, Anton Marsden, Bede McCall, Shane McCarron, Ian McKellar, Chris Nappin, Ann Navarro, Kenichi Numata, Morten Blinksbjerg Nielsen, Allan Odgaard, Matt Oshry, Gerald Oskoboiny, Paul Ossenbruggen, Ernst Paalvast, Christian Pantel, Dimitri Papadopoulos, Steven Pemberton, Lee Anne Phillips, Xavier Plantefeve, Karl Prinz, Andy Quick, Thomas Ribbrock, Ross L. Richardson, Philip Riebold, Erik Rossen, Dan Rudman, Peter Ruevski, Christian Ruetgers, Klaus Johannes Rusch, John Russell, Eric Schindler, J. Schlauch, Christian Schüler, Klaus Alexander Seistrup, Jim Seymour, Kazuyoshi Shimizu, Geoff Sinclair, Jo Smith, Paul Smith, Steve Spilker, Rafi Stern, Michael J. Suzio, Zac Thompson, Oren Tirosh, John Tobler, Loïc Trégan, Jason Tribbeck, Simon Trimmer, Steffen Ullrich, Stuart Updegrave, Charles A. Upsdell, Jussi Vestman, Larry W. Virden, Daniel Vogelheim, Jez Wain, Randy Waki, Paul Ward, Jeff Young, Johannes Zellner, Christian Zuckschwerdt
73b Ground Corner
Holt
Wiltshire
BA14 6RT
United Kingdom
Dave Raggett <dsr@w3.org> is an engineer from Hewlett Packard's UK Laboratories, and works on assignment to the World Wide Web Consortium, where he is the W3C lead for HTML, Math and Voice Browsers.