When you send files via email, social media and elsewhere online, be aware that those files contain metadata that can reveal information about you that you may not want to share. If you wish to remove metadata, there are steps you can take.
What is Metadata?
Metadata is data that defines or describes another piece of data. Metadata by itself is not bad, but it may reveal more about you, your devices, or our organization than you realize. Many devices, such as your computer, camera, or smartphone, automatically embed metadata in any digital files they create. In addition, most software programs or file formats include placeholders or standards for specific types of metadata. A common example is Microsoft Word, which by default is likely to include information about the author, the date when the document was created, and any embedded comments or revisions.
Some examples of metadata include:
- File creation date and time
- The address or geographic location where the file was created
- Your name, your organization’s name, and your computer’s name or IP address
- The names of any contributors to the document or comments they have inserted
- Type of camera you are using and its settings when the photo was taken
- Type of audio or video recording device you are using and its settings when a recording was taken
- Make, model, and service provider of your smartphone
Much of this metadata by itself may not be damaging. In fact, you may deliberately make metadata freely available, such as embedding your name in an image for copyright purposes. However, especially when dealing with sensitive or confidential pieces of information, you should be aware of the metadata that you are revealing to others. When you create a file that includes metadata, there is no telling where that information might find itself in the future.
Best Practices for Metadata
By following some simple steps, you can help to ensure that only information you intend to share with others is actually shared. Some best practices for dealing with metadata include:
- Saving the file in a format that does not store (or has very limited) metadata. For example, instead of sharing a Word document, convert the document into .rtf or .txt file format. For images, use the PNG file format instead of JPEG images.
- Running a metadata cleaner, such as Microsoft Office’s Document Inspector or other special software tools designed to identify and remove metadata.
- Checking the preferences or settings for any application or device you are using. You may be able to limit the amount of metadata they store by changing the default configuration options. For example, you can disable geo-location tracking for your smartphone camera.
- Before you send or post a file, consider the impact if the file contains metadata. This is especially true when posting files such as photos or videos to social networking sites, like Flickr, Twitter, or Facebook.
Identifying and Removing Metadata
On a Windows operating system
Follow these steps to identify metadata on a Windows computer for any file you are working with:
- Right-click on the file.
- View its Properties.
- If there is metadata that you would like to remove, select the Details tab.
- Click Remove Properties and Personal Information.
- Another option is to use Document Inspector, a built-in tool for Microsoft applications, which will identify metadata and give you the option of selectively removing some or all of it.
On a Mac operating system
Remove metadata from a Microsoft Office file on a Mac OS computer by following these steps:
- Click Preferences > Security > Privacy.
- Under the Privacy options heading, select Remove personal information from this file on save.
The Mac OS X application Preview can show you the metadata of any photo by following these steps:
- Open Preview.
- Under Tools, select Show Inspector. Use the More Info Inspector (the small "i" tab) to view metadata.