What Is an OPML File?

How to Open, Edit, and Convert OPML Files

Screenshot of OPML files
OPML Files.

A file with the OPML file extension is an Outline Processor Markup Language file. It's saved in a particular structure using the XML format, and is used to exchange information between applications regardless of the operating system.

The OPML file format is often seen used as the import/export format for RSS feed reader programs. Since a file of this format can hold a collection of RSS subscription information, it's the ideal format for backing up or sharing RSS feeds.

How to Open an OPML File

Almost any program that manages RSS feeds should be able to import OPML files and export OPML files.

Feedly is one example of a free RSS reader that can import OPML files (you can do it through this OPML Import link). The Thunderbird email client should work as well.

If you find an OPML file online and would like to see what's in it, there's a tool called OPML Viewer that will do just that.

Tkoutline and ConceptDraw's MINDMAP can open .OPML files too.

A simple text editor is another way to open OPML files. If possible, Notepad++ is a good choice. Remember, however, that an actual RSS feed aggregator like Feedly is the best way to actually make the OPML feed entries useful (i.e. show you the content that the RSS feeds are from). A text editor is really only good for editing the OPML file or viewing just the text content.

On that note, any XML or text editor can be used to make changes to an OPML file.

You can read more about XML files here.

Note: If you find that an application on your PC does try to open the OPML file but it's the wrong application or if you would rather have another installed program open OPML files, see my How to Change the Default Program for a Specific File Extension guide for making that change in Windows.

How to Convert an OPML File

The Tkouline program mentioned above can be used to convert an OPML file to HTML or XML.

OPML files can also be converted to CSV for use in a spreadsheet program like Microsoft Excel, using this online OPML to CSV converter.

To save the OPML text to JSON, use the free OPML to JSON Converter on BeautifyTools.com.

Pandoc is another OPML converter that can save the XML data from an OPML file to a huge variety of formats like AsciiDoc, markdown, LaTeX, and others.

More Information on the OPML File Format

In a typical OPML file, there's a <head> element that describes the title, owner, or some other metadata information. With an RSS feed, this is normally the article's title. Following that is the <body> tag that holds the content of what the file is describing, and the <outline> element to hold attributes or or other outline sub-elements.

OPML was created by UserLand with the original intent being for a file format that belonged to the word processor tool built into the Radio UserLand software.

Still Can't Open Your File?

If you can't open your file with the suggestions from above, the first thing you should check is that you're actually dealing with an OPML file. Some file extensions look similar to OPML but are in fact not related at all, and therefore do not work with the OPML programs above.

For example, you might really have an OMP file, which could be an Office Manager Document Archive file or an OpenMind Window Document file. Though the file extension looks an awful lot like OPML, they are not the same format and can not open with the same applications.

Tip: The former is a file format created by the Krekeler Office Manager Pro software, and the latter works with MatchWare MindView.

OPAL is a similar file extension that might be confused as an OPML file. It's instead used by Microsoft Office Customization Tool as a Microsoft Office User Settings file to customize how Microsoft Office is installed.

If you need to, see Get More Help for information about contacting me on social networks or via email, posting on tech support forums, and more. Let me know what kinds of problems you're having with opening or using the OPML file and I'll see what I can do to help.