How do I reference or cite definitions from

All FileInfo content is protected by copyright law. Therefore, if you choose to republish content from, you must include an appropriate reference or citation wherever the material is published.


Below are some basic instructions for referencing in different types of publications.

Online: If you reference a file extension or other FileInfo page in a document published on the web, you may place the following text with a link to after the content:

[referenced content]

Information from FileInfo - The File Extensions Database.

Offline: If you reference a page from in a printed publication, you can use the following citation:

[referenced content]

Information retrieved from

In either of the above cases, you may add a link to the actual URL instead of the home page. For example, you may include a link to "" if you reference the PDF file extension page. Just remember to include a valid link wherever you reference content from


Below are guidelines for citing information from, such as in a bibliography or list of references.

Title: You may use the full title or an abbreviated version, such as "PDF File Extension" instead of "PDF File Extension - What is a .pdf file and how do I open it?"

URL When citing, you should include the URL of the exact page you are referencing, such as ""

Author: Since a team of file format experts adds and updates content on, there is no need to reference the author in the citation.

Date: Most file extension pages include an "Updated Date" after the program list for a specific file type. If there is no date displayed with the definition, you may use "2006" as the date.

Below are examples of how to cite the PDF File Extension page using APA and MLA citation styles.


PDF File Extension. (2019, February 13). Retrieved from


"PDF File Extension.", 13 Feb. 2019,

Additional Information

More information about the FileInfo copyright policy can be found on the Terms of Use page.

If you have any questions about using or referencing content from, please contact us.