4MU File

What are 4MU files and how to open them

Are you having problems opening a 4MU file or just wondering what they contain? We explain what these files are used for and show you software that we know can open or otherwise handle your files.

What is a 4MU file?

A .4MU file is a Wikireader Forth Program file.

Files with the extension .4MU are associated with Forth, a programming language developed in the 1970s known for its simplicity, flexibility, and efficiency. It is popularly used in scientific and engineering applications as well as in embedded systems.

The Wikireader, a portable e-reader device released in 2011 and no longer in production, was designed to provide a low-cost, low-power solution for reading and editing Wikipedia articles. For program execution, it relies on .4MU files - specialized programs written in the Forth language.

The Wikireader can run Forth programs from their .4MU files through the device's built-in Forth interpreter.

How to open 4MU files

Important: Different programs may use files with the 4MU file extension for different purposes, so unless you are sure which format your 4MU file is, you may need to try a few different programs.

We have not yet verified any programs for Windows that work with this specific file format. If you know one, please use the 'Suggest a program' link below. Thanks!

Last updated: January 26, 2023

Help us help others

File.org helps thousands of users every day, and we would love to hear from you if you have additional information about 4MU file formats, example files, or compatible programs. Please use the links below or email us at submit@file.org to discuss further.