How to open DEF files

Did your computer fail to open a DEF file? We explain what DEF files are and recommend software that we know can open or convert your files.

What is a DEF file?

Files that contain the .def file extension are most commonly associated with Microsoft Visual C++ definition files. These files list the exports and attributes of a specific program that is linked by an application linker.

The DEF file format is commonly used when creating a dynamic link library during the development of a software application.

The 3D Fassade Plus software application also uses the .def file extension. These DEF files contain definition module files that are used by the software.

A variety of Nova Logic software games also use files with the .def file suffix. These DEF files contain game weapon files that are referenced by the software during a user's gameplay.

Software that will open, convert or fix DEF files

These apps are known to open certain types of DEF files. Since many different programs may use DEF files for different purposes, you may need to try a few of the apps to open your specific DEF file.

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We have not verified any programs that we know for certain can work with DEF-files on Mac. If you know one, please use the Suggest link below and tell us about it!
We have not verified any online services that we know for certain can work with DEF-files. If you know one, please use the Suggest link below and tell us about it!