MHTML
Encyclopedia
MHTML, short for MIME
HTML
, is a web page archive format used to combine
resources that are typically represented by external links (such as images, Flash animations, Java applets, audio files) together with HTML code into a single file. The content of an MHTML file is encoded as if it were an HTML e-mail
message, using the MIME type
s and encoded in base64
. This format is sometimes referred to as MHT, after the suffix .mht given to such files by default when created by Microsoft Word
, Internet Explorer
, or Opera
. MHTML is a proposed standard, circulated in a revised edition in 1999 as RFC 2557.
9.0 web browser. In Opera 9.50, the default saving format for the "Save as" function is MHTML.
requires an extension
to be installed to read and write MHT files. MAFF
https://addons.mozilla.org/en-US/firefox/addon/212/ and UnMHT https://addons.mozilla.org/en-US/firefox/addon/8051 are examples. The MAFF and UnMHT extensions were formerly (in 2006) reported to have compatibility issues with opening files saved by them in Internet Explorer.
Files that are totally compatible with Internet Explorer and other browsers are created by versions 0.14 and later of the maf extension. Internet Explorer-created MHT files render perfectly, and rendering of the divergent Opera-created MHT files has been gradually improved.
UnMHT (version 5.0.0 or greater) offers partial support for MHT files exported from Microsoft Office applications.
Although Firefox does not currently (v3.6.3) include support for MHTML without the use of add-ons, there is source code available for viewing MHTML files within the related Thunderbird
project, indicating that future support in Mozilla software such as Firefox may become available without such add-ons. MHTML support has been filed as an unsolved issue within the Firefox project since 1999, while progress in fixing it seems to be slow moving.
web browser does not support the MHTML format at all.
There is a workaround UnMHT port
for Safari available based on the SIMBL
application enhancement loader and GreaseKit.
's Konqueror
web browser does not support MHTML files. (There is a side project mhtconv that lets one use MHTML with Konqueror for both 3.x and 4.x KDE branches).
3.4 (on devices such as the Sony Ericsson K850) can view and save MHTML files.
since Word 2002 can open and save MHTML documents. A converter is available from Microsoft to enable Word 2000 to open MHTML files, and an add-on is available to allow it to save MHTML files.
MHTML is also supported by Microsoft Office Viewers in Microsoft Word
, Microsoft Publisher
, Microsoft Excel
, and Microsoft PowerPoint
. Microsoft's HTML editors, such as FrontPage
, Expression Web
, and SharePoint Designer
, do not support editing MHTs.
A Windows
application called Blocknote supports editing MHTs.
On the Linux
platform, a utility called kmhtConvert is available to convert MHTML files to the KDE
Web Archive format.
MIME
Multipurpose Internet Mail Extensions is an Internet standard that extends the format of email to support:* Text in character sets other than ASCII* Non-text attachments* Message bodies with multiple parts...
HTML
HTML
HyperText Markup Language is the predominant markup language for web pages. HTML elements are the basic building-blocks of webpages....
, is a web page archive format used to combine
File archiver
A file archiver is a computer program that combines a number of files together into one archive file, or a series of archive files, for easier transportation or storage...
resources that are typically represented by external links (such as images, Flash animations, Java applets, audio files) together with HTML code into a single file. The content of an MHTML file is encoded as if it were an HTML e-mail
HTML e-mail
HTML email is the use of a subset of HTML to provide formatting and semantic markup capabilities in email that are not available with plain text.Most graphical email clients support HTML email, and many default to it...
message, using the MIME type
multipart/related. The first part of the file is normally encoded HTML; subsequent parts are additional resources identified by their original URLUniform Resource Locator
In computing, a uniform resource locator or universal resource locator is a specific character string that constitutes a reference to an Internet resource....
s and encoded in base64
Base64
Base64 is a group of similar encoding schemes that represent binary data in an ASCII string format by translating it into a radix-64 representation...
. This format is sometimes referred to as MHT, after the suffix .mht given to such files by default when created by Microsoft Word
Microsoft Word
Microsoft Word is a word processor designed by Microsoft. It was first released in 1983 under the name Multi-Tool Word for Xenix systems. Subsequent versions were later written for several other platforms including IBM PCs running DOS , the Apple Macintosh , the AT&T Unix PC , Atari ST , SCO UNIX,...
, Internet Explorer
Internet Explorer
Windows Internet Explorer is a series of graphical web browsers developed by Microsoft and included as part of the Microsoft Windows line of operating systems, starting in 1995. It was first released as part of the add-on package Plus! for Windows 95 that year...
, or Opera
Opera (web browser)
Opera is a web browser and Internet suite developed by Opera Software with over 200 million users worldwide. The browser handles common Internet-related tasks such as displaying web sites, sending and receiving e-mail messages, managing contacts, chatting on IRC, downloading files via BitTorrent,...
. MHTML is a proposed standard, circulated in a revised edition in 1999 as RFC 2557.
Browser support
Some browsers support the MHTML format, either directly or through third-party extensions, but the process for saving a web page along with its resources as an MHTML file is not standardized. Due to this, a web page saved as an MHTML file using one browser may render differently on another.Internet Explorer
Microsoft Internet Explorer was the first browser to support saving web pages with all their resources to a single MHTML file as of its version 5.0 released in 1999.Opera
Support for saving a web page with its resources as an MHTML file was made available in the OperaOpera (web browser)
Opera is a web browser and Internet suite developed by Opera Software with over 200 million users worldwide. The browser handles common Internet-related tasks such as displaying web sites, sending and receiving e-mail messages, managing contacts, chatting on IRC, downloading files via BitTorrent,...
9.0 web browser. In Opera 9.50, the default saving format for the "Save as" function is MHTML.
Firefox
Mozilla FirefoxMozilla Firefox
Mozilla Firefox is a free and open source web browser descended from the Mozilla Application Suite and managed by Mozilla Corporation. , Firefox is the second most widely used browser, with approximately 25% of worldwide usage share of web browsers...
requires an extension
Extension (computing)
Software extension, is a file containing programming that serves to extend the capabilities of or data available to a more basic program. It is a kind of list of commands which are directly included in the program. This term often coincides with the plug-in...
to be installed to read and write MHT files. MAFF
Mozilla Archive Format
The Mozilla Archive Format is a web page archiving format provided by Firefox for saving one or more web pages together with its associated audio, video, and other related web resources in a single file. It is not the same as the MHTML file format, which uses MIME encoding to store all the...
https://addons.mozilla.org/en-US/firefox/addon/212/ and UnMHT https://addons.mozilla.org/en-US/firefox/addon/8051 are examples. The MAFF and UnMHT extensions were formerly (in 2006) reported to have compatibility issues with opening files saved by them in Internet Explorer.
Files that are totally compatible with Internet Explorer and other browsers are created by versions 0.14 and later of the maf extension. Internet Explorer-created MHT files render perfectly, and rendering of the divergent Opera-created MHT files has been gradually improved.
UnMHT (version 5.0.0 or greater) offers partial support for MHT files exported from Microsoft Office applications.
Although Firefox does not currently (v3.6.3) include support for MHTML without the use of add-ons, there is source code available for viewing MHTML files within the related Thunderbird
Mozilla Thunderbird
Mozilla Thunderbird is a free, open source, cross-platform e-mail and news client developed by the Mozilla Foundation. The project strategy is modeled after Mozilla Firefox, a project aimed at creating a web browser...
project, indicating that future support in Mozilla software such as Firefox may become available without such add-ons. MHTML support has been filed as an unsolved issue within the Firefox project since 1999, while progress in fixing it seems to be slow moving.
Safari
As of version 3.1.1 (released 2008-05-28) onwards, Apple Inc.'s SafariSafari (web browser)
Safari is a web browser developed by Apple Inc. and included with the Mac OS X and iOS operating systems. First released as a public beta on January 7, 2003 on the company's Mac OS X operating system, it became Apple's default browser beginning with Mac OS X v10.3 "Panther". Safari is also the...
web browser does not support the MHTML format at all.
There is a workaround UnMHT port
Porting
In computer science, porting is the process of adapting software so that an executable program can be created for a computing environment that is different from the one for which it was originally designed...
for Safari available based on the SIMBL
SIMBL
SIMBL , is an application enhancement loader for Mac OS X developed by Mike Solomon. It helps third-party developers modify and add functionality to applications developed with the Cocoa environment without access to the source code...
application enhancement loader and GreaseKit.
Konqueror
As of version 3.5.7 (released 2007-05-02), KDEKDE
KDE is an international free software community producing an integrated set of cross-platform applications designed to run on Linux, FreeBSD, Microsoft Windows, Solaris and Mac OS X systems...
's Konqueror
Konqueror
Not to be confused with the Conqueror web browser.Konqueror is a web browser and file manager that provides file-viewer functionality for file systems such as local files, files on a remote ftp server and files in a disk image. It is a core part of the KDE desktop environment...
web browser does not support MHTML files. (There is a side project mhtconv that lets one use MHTML with Konqueror for both 3.x and 4.x KDE branches).
ACCESS NetFront
NetFrontNetFront
NetFront Browser is a mobile browser for embedded devices, developed by Access Co. Ltd. of Japan, and was designed to function as an embedded browser....
3.4 (on devices such as the Sony Ericsson K850) can view and save MHTML files.
Google Chrome
Viewing MHTML files in the recent versions of Google Chrome is supported, but still not for saving.Editing support
All versions of Microsoft WordMicrosoft Word
Microsoft Word is a word processor designed by Microsoft. It was first released in 1983 under the name Multi-Tool Word for Xenix systems. Subsequent versions were later written for several other platforms including IBM PCs running DOS , the Apple Macintosh , the AT&T Unix PC , Atari ST , SCO UNIX,...
since Word 2002 can open and save MHTML documents. A converter is available from Microsoft to enable Word 2000 to open MHTML files, and an add-on is available to allow it to save MHTML files.
MHTML is also supported by Microsoft Office Viewers in Microsoft Word
Microsoft Word
Microsoft Word is a word processor designed by Microsoft. It was first released in 1983 under the name Multi-Tool Word for Xenix systems. Subsequent versions were later written for several other platforms including IBM PCs running DOS , the Apple Macintosh , the AT&T Unix PC , Atari ST , SCO UNIX,...
, Microsoft Publisher
Microsoft Publisher
Microsoft Publisher is a desktop publishing application from Microsoft. It is an entry-level application, differing from Microsoft Word in that the emphasis is placed on page layout and design rather than text composition and proofing...
, Microsoft Excel
Microsoft Excel
Microsoft Excel is a proprietary commercial spreadsheet application written and distributed by Microsoft for Microsoft Windows and Mac OS X. It features calculation, graphing tools, pivot tables, and a macro programming language called Visual Basic for Applications...
, and Microsoft PowerPoint
Microsoft PowerPoint
Microsoft PowerPoint, usually just called PowerPoint, is a non-free commercial presentation program developed by Microsoft. It is part of the Microsoft Office suite, and runs on Microsoft Windows and Apple's Mac OS X operating system...
. Microsoft's HTML editors, such as FrontPage
Microsoft FrontPage
Microsoft FrontPage was a WYSIWYG HTML editor and web site administration tool from Microsoft for the Microsoft Windows line of operating systems. It was branded as part of the Microsoft Office suite from 1997 to 2003...
, Expression Web
Microsoft Expression Web
Microsoft Expression Web, code-named Quartz, is an HTML editor and general web design software product by Microsoft. It is part of the Expression Studio suite....
, and SharePoint Designer
Microsoft SharePoint Designer
Microsoft SharePoint Designer is a specialized HTML editor and web design freeware for creating or modifying Microsoft SharePoint sites and web pages. It is a part of Microsoft SharePoint family of products...
, do not support editing MHTs.
A Windows
Microsoft Windows
Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
application called Blocknote supports editing MHTs.
On the Linux
Linux
Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
platform, a utility called kmhtConvert is available to convert MHTML files to the KDE
KDE
KDE is an international free software community producing an integrated set of cross-platform applications designed to run on Linux, FreeBSD, Microsoft Windows, Solaris and Mac OS X systems...
Web Archive format.
See also
- Mozilla Archive FormatMozilla Archive FormatThe Mozilla Archive Format is a web page archiving format provided by Firefox for saving one or more web pages together with its associated audio, video, and other related web resources in a single file. It is not the same as the MHTML file format, which uses MIME encoding to store all the...
- An alternative for attaching resources to an HTML document is the Data: URI schemeData: URI schemeThe data URI scheme is a URI scheme that provides a way to include data in-line in web pages as if they were external resources. It tends to be simpler than other inclusion methods, such as MIME with cid or mid URIs. Data URIs are sometimes called Uniform Resource Locators, although they do not...
defined in IETF standard RFC 2397. - In January 2011 Microsoft announced a vulnerability in all then-supported versions of Windows (XP SP3, 7, Vista, Server 2003, Server 2008) related to MHTML.
External links
- MHTML standard explained
- RFC 2557 (1999) — MIME Encapsulation of Aggregate Documents, such as HTML (MHTML)
- RFC 2110 (1997, Obsolete) — MIME E-mail Encapsulation of Aggregate Documents, such as HTML (MHTML)
- MHT-rip - A program to view MHTML files on Linux