How to Open CFG File in Windows and macOS

By Bishwo Tamli Updated December 4, 2022

You won’t be able to open CFG files by default because your computer hasn’t assigned a default application to open it. If you try to open it, you will be told to select a corresponding application with which you want to open the file.

If you need to view or edit .cfg files for any reason, it is essential to know exactly what these files are and which applications can run them. You may also need to use different applications to open a CFG file, depending on whether it’s in a text or binary file format.

What is a CFG File?

A CFG file stands for a Configuration file. These files usually include a list of options or settings of the software along with their set values. Every software associated with .cfg files will check them to specify the settings that the application uses.

Most CFG files use text-based formats like XML or JSON file format depending on the developer. Opening and editing configuration files that use standard formats are relatively easy as you can easily find numerous information on how they work.

In some cases, developers may also choose to use custom text or other formats. You can only edit such files if the developers have released guides to their custom format or by using the trial and error method to learn how they work.

Developers often use custom file formats to discourage the public from editing the software’s .cfg files. It is because any mistake in changing a software’s configuration file can easily lead to the software malfunctioning, misbehaving, or completely stop working.

How to Open a CFG File?

Opening a CFG is as easy as opening any other file on your computer. You only need to know which applications can open .cfg files and guide the computer to access the file from that application.

However, the methods and applications you can use to open CFG files will differ depending on your operating system.

On Windows

Most CFG files use simple text formats, so you can use any text editor to open and edit the file in Windows. You can use pre-installed applications like notepad and Wordpad.

Additionally, if you often edit large .cfg files, you can use more advanced text editors like Notepad++ or Sublime Text for convenience.

Here’s how you can open CFG files using any text editor:

Open File Explorer.
Navigate to the .cfg file you want to open.
Right-click the file. (If a text editor is already assigned as the default application to open CFG files, you can double-click to open it.)
Select Open With.
Select the application you want to use to open that CFG file from the list of applications.
If your preferred text editor is not on that list, do the following:
- Click on More apps.
- Scroll down and select Look for another app on this PC.
- Navigate to the application you want to use. (If you don’t know where the app is located, search for it in the search bar, right-click it, and select Open file location.)
- Select the application and click Open.
If you want to use that text editor as the default application for opening CFG files, check the Always use this file to open .cfg files option.
Click OK.

Alternatively, you can try to open .cfg files directly from the text editor. Here’s how you can do so:

Open your preferred text editor.
Press Ctrl + O to open your file.
Navigate to the location of the .cfg file.
Select it and click on Open.

Note: Some programs like Wordpad will convert the CFG files to TXT files if you save them as is. So, you will have to save it as a CFG file manually. Also, if the CFG file is protected, you won’t be able to overwrite the file while saving it. To get around this issue, you will need to run your text editor with administrator access.

On macOS

Like Windows, you can use just about any text editor to open .cfg files on Mac. You can also use advanced text editors that provide more features for in-depth editing.

Launch Finder.
Navigate to the .cfg file you want to open.
Right-click the file and select Open With.
Click on Other.
In the Applications folder, choose the text editor with which you want to open that CFG file.
If you want to assign that text editor as the default app for opening CFG files, check the Always open with option.
Select Open.

While saving the CFG file, ensure your text editor is saving it in CFG format and isn’t changing it to .txt format.

How to Open CFG Files That Use Binary Format?

In rare cases, your .cfg files may not use text but binary file format. If you use text editors, which usually don’t support binary editing, they will display some incomprehensible data. It is because binary file formats are only meant to be understood by computers, not humans.

Nonetheless, you can use Hex editors to open and edit such files. These applications display the information within binary files in a graphical manner and allow you to edit them easily.

The displayed information is in Hexadecimal format, and for people who don’t know binary file editing and associated languages like assembly, we recommend you not to edit such .cfg files.

If you want to edit binary files regardless of the risks, some simple and handy Hex editors are Hackman and HxD Hex Editor. After downloading your preferred app, you can use the same method as above to open your CFG files.