ONE File Type

- The quick facts

What are ONE files and how to open them

Are you having problems opening an ONE file or just wondering what they contain? We explain what these files are used for and show you software that we know can open or otherwise handle your files.

What is an ONE file?

ONE files have multiple uses, and Microsoft OneNote Note is one of them.

Microsoft OneNote Note

The files that contain the .one file extension are most commonly created by the Microsoft OneNote computer software application.

OneNote allows users to take free-form electronic notes on their computer by using typed or handwritten input. These notes are then saved to the user's hard drive with the .one file extension. The OneNote application also allows for audio recordings and advanced searching options. Files with the .one extension usually contains text notes that have been saved within the application. Still, they may also include pasted clipboard contents and audio or video clips that have been incorporated into a OneNote file.

How to open ONE files

Important: Different programs may use files with the ONE file extension for different purposes, so unless you are sure which format your ONE file is, you may need to try a few different programs.

While we have not verified the apps ourselves yet, our users have suggested 7 different ONE openers which you will find listed below.

Last updated: January 25, 2022

More file formats using the ONE extension

Through our research of ONE files, we know that the following formats exist. However, we have not yet analyzed them in detail.

  • SEMONE Compressed Archive
  • Sequencer One Song

Various apps that use files with this extension

These apps are known to open certain types of ONE files. Remember, different programs may use ONE files for different purposes, so you may need to try out a few of them to be able to open your specific file.

Microsoft OneNoteMicrosoft OneNoteUser submitted
Microsoft OfficeMicrosoft OfficeUser submitted
Adobe AcrobatAdobe AcrobatUser submitted
Hancom OfficeHancom OfficeUser submitted
Microsoft Office Mondo - EnglishMicrosoft Office Mondo - EnglishUser submitted
V-ToolsV-ToolsUser submitted
CLSCLSUser submitted

Help us help others helps thousands of users every day, and we would love to hear from you if you have additional information about ONE file formats, example files, or compatible programs. Please use the links below or email us at to discuss further.