Windows
Compatible applications
Quick Facts
Basic information about this file format
Extension
.LISP
File Type
Lisp Source Code File
Category
Programming
Best first step
Use compatible software
Quick Summary
A practical overview of the .lisp file format
The .lisp file extension is used for source code files written in the Lisp programming language, which is one of the oldest high-level programming languages still in active use today. Standing for 'List Processing,' Lisp is renowned for its unique prefix notation and heavy use of parentheses to def…
File extension
.LISP
File type
Lisp Source Code File
Category
Programming
Recommended action
Open with a trusted compatible app
How to open a .lisp file
Start with a trusted app that supports this format
- Check the file extension carefully and confirm that the file name really ends with .lisp.
- Use software that supports this file type. If one app does not work, try another compatible program for the same platform.
- Update the application if the file was created by a newer version of the software.
- Scan files from unknown sources before opening them, especially documents, archives, scripts, installers, and executable files.
What is a .lisp file?
File extension details and usage information
The .lisp file extension is used for source code files written in the Lisp programming language, which is one of the oldest high-level programming languages still in active use today. Standing for 'List Processing,' Lisp is renowned for its unique prefix notation and heavy use of parentheses to define nested data structures and code blocks. These files contain plain text instructions that are either interpreted or compiled by a Lisp environment. While there are many dialects of Lisp, the .lisp extension is most commonly associated with Common Lisp. The format is heavily utilized in artificial intelligence research, symbolic mathematics, and for scripting within complex applications like AutoCAD or the Emacs text editor. Because the files are stored in a plain text format, they are highly portable across different operating systems. Developers typically use specialized editors that support S-expression manipulation to manage the language's specific syntax requirements effectively, ensuring proper indentation and parenthesis balancing.
Software Compatibility
Programs that may open or work with .lisp files
macOS
Compatible applications
Linux
Compatible applications
Mobile
Mobile applications
Can .lisp files be converted?
Options for saving or exporting this file to another format
In many cases, a .lisp file can be converted by opening it in compatible software and using an option such as Save As, Export, or Convert. The available output formats depend on the file type and the application used.
- Use the original software that created the file when possible.
- Check whether the application supports exporting to common formats.
- Be careful with online converters when working with private, business, or sensitive files.
- If conversion fails, the file may be corrupted, incomplete, encrypted, or not actually a .lisp file.
Why can't I open a .lisp file?
Common reasons this file type may not open correctly
Wrong software
The file may require a specific program that supports the .lisp format.
Incorrect extension
The file extension may have been renamed manually, even though the actual file format is different.
Corrupted file
The file may be incomplete, damaged during download, or transferred incorrectly.
Outdated app
Your software may need to be updated before it can open newer versions of this file format.
Frequently Asked Questions
Common questions about .lisp files
To open a .lisp file, use software that supports this file format.
- Visual Studio Code
- GNU Emacs
- Portacle
- Notepad++
- Steel Bank Common Lisp (SBCL)
Open the file in compatible software and look for options such as Save As, Export, or Convert. If no export option is available, the file may require a specialized converter or the original application that created it.
- Verify that the file extension is correct.
- Install or update compatible software.
- Try another application that supports this format.
- Check whether the file is corrupted, incomplete, or encrypted.
A file extension alone does not guarantee whether a file is safe or unsafe. Only open files from trusted sources, scan unknown files before opening them, and be especially careful with executable, script, archive, and document files.
File safety tips
Use caution with unknown files
Only open files from trusted sources. Before opening a .lisp file, scan it with antivirus software, verify that the file extension is expected, and avoid running unknown executable, installer, macro-enabled document, or script files.