File extension is the group of letters after a period at the end of a file name, indicating the format of the file. For example, .TXT, .JPG, .PNG, .DOCX, .ZIP, .RAR, .MP4, .AVI, etc. are all common file extensions in computing. In this guide, you will learn how to show file extensions for all file types in Windows 11 (hidden by default) and how to change or remove the file extension of a file.
Also see: How to Change Default App For File Extension in Windows 11
Will changing the file extension of a file changes its file format?
The format of a file cannot be changed by simply changing its file extension (without properly converting it). The format of a file will retain even after its extension is changed or removed. In some cases, changing the file extension of a file forcefully and incorrectly may corrupt or break the file, making it unreadable and unusable.
Why would you want to change or remove file extension of a file?
This guide is for users who know that a file has incorrect file extension or the file extension is missing. If you were asked to change or remove the file extension of a file but you couldn’t see the file extension at the end of the file’s name, follow the instructions below to allow Windows 11 to display file name extensions for all files, so that you can make changes to the file extension of any file.
Another common reason users would want to remove the file extension of a file is to hide the file type of the file to prevent anyone else from knowing what the file is and how to open the file. If a file doesn’t have a file extension when it’s supposed to have one, Windows wouldn’t know what app it should open the file in, thus showing the “how do you want to open this file” pop up. A file without a file extension will also appear as a white icon instead.
Change or remove file extension in Windows 11
To be able to add, change or remove file extension of a file in Windows 11, first you need to be able to see the file extension in the file name. Since file extension is hidden by default in Windows 11, you need to enable it through File Explorer folder options to allow Windows to display the file extension for each file. Here’s how to do it.
- In Windows 11, open This PC or File Explorer.
- On the toolbar, click View and hover your mouse cursor over Show. Then, click File name extensions to enable it. If the option is enabled, it will have a tick next to it.
After enabling the show file name extensions option, Windows will start showing the file extension for each individual file. You can now figure out the file type of each file and edit the file extension of any file.
If you want to revert the change and hide the file extensions for all files, simply repeat the steps above and click the “File name extensions” option again to remove the tick next to it.
How to change file extension of a file in Windows 11
To change the file extension of a file, simply right-click the file and select Rename, or alternatively, select the file and press F2. Then, change the letters after the period in the filename to the file extension you want to change the file to.
Windows will then prompt you a warning telling you that the file might become unusable if you change its file name extension. Click Yes to confirm the change.
Remove the file extension of a file
To remove the file extension of a file, right-click the file and select Rename. In the file name, delete the letters after the period and the period itself. When Windows prompt for confirmation, select Yes to confirm the change.
The icon of the file with removed file extension will turn into a white icon and have the type of file changed to just “File”. Windows will no longer know what file type the file is and how to open the file. Depending on the file, you may still be able to run the file in the reader or player app that used to open it without having any file extension.
You can add the file extension back to the file by simply renaming it again and adding the period and extension to the end of the filename.
Should I keep the “show file name extensions” option enabled?
For security reason, we would recommend to keep the option enabled so that you know the file type of a file before opening it. In fact, users should enable show file name extensions as soon as they start using Windows. Microsoft should allow file name extension to be displayed by default so that users can identify if a file is the file format they want to open before opening it.
This is because hackers can exploit this and fake a file since users couldn’t see the file extensions. For example, if an image file you download from the Internet supposed to be in image file format but turns out to be a .bat script file, since you can’t see the file extension, you may risk getting your computer infected by unknowingly opening the malicious file.