An extension is required for programs or files in order for the operating system to assign software to run. In layman’s terms, an extension tells the computer what the structure of the file is and what tool/software it needs to run or execute it. But what if you want to open a file that doesn’t have an extension on Windows 10 or 11?
Without the file extension, the computer will be confused, or ambiguous in technical terms, and may not allow the file to be run.
Each executable file on a computer requires a unique extension. The filename is the standard nomenclature for a file.file_extention. The dot (.) character separates the filename from the file extension.
The file will not execute if the operating system cannot read the file extension or if it is not existent.
But what if you want to run a file that doesn’t have a file extension? How do you open files that don’t have extensions?
on this post, we’ll go through how to open a file with no extension on Windows 10 or Windows 11.
Contents
Before we can open files without extensions, we must first learn how to open a regular file on Windows 10/11.
We have described three methods for a user to open a file:
By double-clicking the file you wish to open
Right-click and select Open.
By picking the desired file and hitting the Enter key
Note: Please keep in mind that you will still want appropriate software to run that file effectively. For example, if you want to open a JPG file, you will need a proper image viewer to do so.
But what if your file doesn’t have a file extension? Let us investigate!
How to Open a File With No Extension in Windows 10 and 11?
If you come across a file that does not have a file extension, you will be unable to open it using the three techniques described above. To correctly open the file, you must first determine its type, which will provide the appropriate extension.
After determining the file type, you may manually append the extension after the dot(.) and run the file with appropriate software. If you do not have appropriate software to open the file, you may need to install software that can execute the file.
So, to determine the file type, which will indicate the extension, we have given various tools below:
1. File Identifier From Toolsley
Toolsley provides a free utility for determining the kind of file, after which you may apply an appropriate extension.

- To utilize this tool, you must first go to Toolsley’s official website.
- The file must then be uploaded without the extension.
- To upload a file, click the Select a file option or drag and drop it.
- Once you’ve submitted the file, the File Identifier will begin analysing it and display the file extension.
2. CheckFileType Online
CheckFileType Online is another online file extension-finding tool on our list. In a few simple steps, you may use this program to determine the extension of your file.

To proceed, follow the steps outlined below:
- To utilize this program, go to the official CheckFileType Online page.
- To upload the file, click anywhere in the box, then go to and pick the file on your computer.
- You may also upload the file by dragging and dropping it into the website’s upload box.
- When you’ve finished uploading the file, click the Check File Type button. A new tab will appear, displaying the extension of the uploaded file.
Note: For this program, the maximum upload size of a file with an unknown extension is 16 MB.
3. Detect File Type
This program is a multi-purpose tool that can help you locate an unfamiliar or incorrect file extension.

To use this tool:
- Visit Detect File Type’s official website
- Then, using the Browse option, upload the file.
- After uploading the file, click the “Detect File Type” button.
- Following that, the program will open a new tab in your browser, where you will find the recommended file type and extension.
4. Online TrID File Identifier
This program offers several unique file extension identifying characteristics. The Online TrID File Identifier studies the file and then displays a percentage of the potential file extensions of the submitted file.
To use this tool follow the steps given below:
- Visit the Online TrID File Identifier Website
- Then, to upload the file, click the Browse option.
- After uploading, click on the Start button to begin the analysis of the file.
Note: This program has a maximum upload limit of 10 MB for files with unknown extensions.
You may also save this tool to your smartphone if you regularly need to detect file extensions. The utility is accessible for installation on the internet and is simple to use.
5. FILExt
Another free online file identification tool is FILExt. You can quickly determine the extensions of unfamiliar file formats with this program.
To use this tool:
- You must go to FILExt’s official website, filext.com.
- Then, scroll down until you locate the Choose your file button.
- Then you must click that button and navigate to the file on your computer to upload it to the website.
- You may also upload files by dragging and dropping them.
- FILExt will automatically analyse and create a preview of the file when you upload it.
- The preview page will include information about the file.
- The file extension will be shown in the preview.
- Then, by selecting the “Save as” option, you may download the file in a compatible format.
Note: Please keep in mind that you may only download the file if the file format is included in the Save as a list.
If you have the correct software and have appended the file with the missing extension with a valid file extension, you should have no trouble opening it.
However, if you wish to examine a file extension on Windows, you must allow them in the file explorer settings.
So, here’s how to enable file extensions in Windows 10 and 11:
How To Enable File Extensions in Windows 11?
Simply change the File Explorer display mode to allow file extensions in Windows 11.
Follow the instructions below to change the view mode:
- Open the Windows File Explorer
- Head to “View > Details.”
- The file extensions will then appear in the Type column.

If you do not want to alter the display mode in Windows File Explorer, you may activate the file extension by doing the following steps:
- Open File Explorer
- Click on the three horizontal dots on the ribbon
- Click on “Options”

- To do so, go to the “View” tab and uncheck the “Hide extensions for unknown file types” box.
- Click “Apply” and finally click OK

When you’re finished, you’ll see the file extensions in any view mode you choose in Windows 11.
How To Enable File Extensions in Windows 10?
Similarly to Windows 11, you must change the display mode or use the Hide file extensions option. Although the steps are identical, the method differs somewhat.
To change the view mode in Windows 10, follow these steps:
- Open the File Explorer
- Go to “View > Details.”
- When you change the view mode to Details, the file extensions will be shown in the Type column.
You may also allow the file extensions by unchecking the Hide file extensions box in Folder Options. To do so, follow the instructions below:
- Open the File Explorer
- Go to the View menu and select “Options > Change folder and search options.”
- The Folder Options box will then appear.
- Then go to the View tab and uncheck the “Hide extensions for known file types” box.
- Then click Apply and finally click OK
If you followed the instructions above carefully, you should have enabled file extensions in Windows 10 by now.
Conclusion
An operating system requires file extensions to determine whether software is required to access or operate a file. The operating system cannot open a file that does not have a file extension.
In this post, we discussed how to use several online file extension searching tools to determine the file extension and kind of file.
We also discussed how to activate the viewing of file extensions on Windows 10 and 11 devices.