JNLP File Extension
Java Web Start Format
- File Type jnlp
- Developer Oracle
- Popularity
- Application PSPad
- Category Settings Files
- Format XML
What is a JNLP file?
The JNLP file extension is linked to Java Web Start Format and belongs to the Settings Files category, which includes 1190 files.
The Java Web Start Format (JNLP), created by Oracle, is one of file format they developed, and they also built 36 programs to support them.
JNLP files are supported by Windows, Linux and Mac OS. When working with JNLP files, you can rely on 6 programs, including Java, PSPad and Sublime Text.
MIME types
- application/x-java-jnlp-file
Programs that support JNLP files
How to open a JNLP file?
If you can’t open a JNLP file, it is usually because the necessary software is missing. To resolve the issue, select the right program from the list for your operating system. Then go to the official website of the developer, download the software, and install it.
The most popular programs for working with JNLP files are Java, PSPad and Sublime Text. To install the latest version of PSPad on your computer, visit the Jan Fiala website where you can download the version available for all operating systems.
Following installation, JNLP files should be automatically opened with PSPad.
Set PSPad as your default JNLP viewer
Changing the default program in Windows
- Right-click on your JNLP file, then choose the "Open with" option and select "Choose another application" from the available options;
- From the list of applications in the pop-up window, find and select PSPad as your desired application;
- Check the "Always use this app" checkbox, and then click "OK" to set your chosen app as the default for opening JNLP files.
Set default app to open files on Mac
- Right-click or Control + left-click on the desired JNLP file to open a menu of available actions;
- Select "Open in application" and click "Other";
- Look at the bottom of the window, where you will see the "Enable" menu. "Recommended Programs" will be selected as the default option;
- Within this menu select "All Programs" and navigate to PSPad. Check the box next to "Always open in app" to make sure it’s the default option.
How to edit a JNLP file?
To edit JNLP files, you need to install specialized software that allows you not only to open but also to modify settings files. Online JNLP editors usually provide fewer features than software created specifically for Java Web Start Format.
Best JNLP editors in 2026
Taking into account the provided details, we have prepared a list of JNLP editors that match your needs.
| JNLP Editor Software | Developer | Platforms | Overall Rating |
|---|---|---|---|
| PSPad | Jan Fiala | Windows | 4.7 out of 5 (41 review) |
| Notepad++ | Notepad++ Team | Windows | 4.6 out of 5 (37 reviews) |
| Sublime Text | Sublime HQ Pty | Windows, Mac OS, Linux | 4.6 out of 5 (39 reviews) |
| Atom | - | Windows, Mac OS, Linux | 4.1 out of 5 (36 reviews) |
Solving Common JNLP File Challenges
When issues arise with JNLP files, they can generally be fixed with small software tweaks. Use the troubleshooting tips below to help resolve them.
What are the warning signs that my JNLP file may be corrupted?
Corrupted JNLP settings files may have one or more of the following symptoms:
- Error messages appear during the course of working with the file;
- Poor performance when editing a file in Notepad++;
- Attempts to open the file result in errors or failed results;
- Unexplained increase in JNLP file size;
- The file causes PSPad or other programs to hang or crash during operation;
Why does PSPad crash?
PSPad crashes can be caused by outdated software. Keep your Jan Fiala products up to date by installing the latest updates.
A simple restart of your computer can often fix many common problems, which is why it is the recommended first step before making any adjustments to your software settings.
How to repair a corrupted JNLP file?
Use a data recovery program to open the damaged JNLP file and from the menu choose "Repair" function to start the repair process. Please be patient while the recovery process completes, which will automatically restore the damaged settings files.