FTN File Extension
Fortran Source Code Format
- File Type ftn
- Popularity
- Application Sublime Text
- Category Developer Files
- Format Text
What is a FTN file?
The FTN file extension is linked to Fortran Source Code Format and belongs to the Developer Files category, which includes 1166 files.
FTN files are compatible with various operating systems, including Mac OS, Windows and Linux. To open a FTN file, you can choose from 3 programs such as Sublime Text, Windows Notepad and Intel Visual Fortran Compiler.
Programs that support FTN files
How to open a FTN file?
If you cannot open a FTN file, it is most often due to missing software. Select a program from the list according to your operating system. Then go to the official website of the program developer, download it, and install it on your device.
Sublime Text, Windows Notepad and Intel Visual Fortran Compiler are recognized as the most popular software solutions for dealing with FTN files. To set up the newest version of Sublime Text on your device, simply go to the official Sublime HQ Pty website. There you can download the edition compatible with every operating system.
Once installed, Sublime Text will be set as the default program, and FTN files will open automatically.
Set Sublime Text to open FTN by default
Setting a default program by file type in Windows
- Right click on your FTN file, then select "Open with" and click "Choose another application";
- Find the Sublime Text application in the pop-up window and select it as your preferred program;
- Select the "Always use this application" check box and click "OK" to save your selection as the default application for opening FTN files.
Change default apps on Mac
- Right-click or use Control + Left-click on the desired FTN file to access the file’s context menu;
- Select "Open in application" and click "Other";
- At the bottom of the window, find the "Enable" menu, where "Recommended Programs" is already selected by default;
- Within this menu, select "All Programs" and then locate Sublime Text. Check the box next to "Always open in app" to set it as the default program.
How to edit a FTN file?
Editing FTN files requires installing professional software that lets you open and edit developer files. Online editors have more limitations compared to dedicated Fortran Source Code Format programs.
Best FTN editors in 2026
Considering the mentioned criteria, we have compiled a list of FTN editors that may suit your needs.
| FTN Editor Software | Developer | Platforms | Overall Rating |
|---|---|---|---|
| Sublime Text | Sublime HQ Pty | Windows, Mac OS, Linux | 4.6 out of 5 (39 reviews) |
| Windows Notepad | Microsoft | Windows | 4.2 out of 5 (37 reviews) |
Easy FTN Troubleshooting
Certain problems with FTN files can be conveniently fixed with small software tweaks. Here are some helpful tips to address them.
What are the steps to repair a damaged FTN file?
Open the corrupted FTN file in a recovery program and select the "Repair" menu item. Please be patient while the recovery process completes, which will automatically restore the damaged developer files.
How do I know if my FTN file is corrupted?
Corrupted FTN developer files may show the following signs:
- Attempts to open the file result in errors or failed results;
- Editing the archive in Sublime Text is accompanied by slow performance or delays;
- The file causes Sublime Text or other programs to hang or crash during operation;
- Unexplained increase in FTN file size;
- Error messages appear while working with the file;
What are the reasons behind Sublime Text crash?
The likely cause of Sublime Text crashing is lack of software updates. Install the latest updates available for Sublime HQ Pty products.
Restarting your computer is often an effective solution to resolve various common problems. Therefore, it is recommended to do so before making any changes to the software configuration.