Files with def extension are usually encountered as definition files used SmartWare, Visual Studio and other apps.

There are 5 other file types using
the DEF file extension!

empty icon.def - Data Entry/Review Module file

empty icon.def - NovaLogic game weapon profile

empty icon.def - ESwin wizard file

empty icon.def - id Tech 6 video settings

empty icon.def - IOBit Malware Fighter definitions

DEF file extension - Definition data

What is def file? How to open def files?

File type specification:

Various data file type icon Various data file type

File extension def is commonly used for so called definition files. These file contains various settings that define certain characteristic ,or operation parameters for programs, devices or their part. Such files are used by many different programs. Sometimes also used for export purposes.

For example module-definition files provide the linker with information about exports, attributes, and other information about the program to be linked. The def file is most useful when building a DLL.

The default software associated to open def file:

Visual C++ icon

Microsoft Corporation logoVisual C++  Microsoft Windows software

Company or developer:
Microsoft Corporation

Visual C++ is integrated development environment for C and C++ programming language used to create Windows and .NET applications.

Microsoft Visual Studio icon

Microsoft Corporation logoMicrosoft Visual Studio  Multiplatform software

Company or developer:
Microsoft Corporation

Microsoft Visual Studio is an integrated development environment (IDE) used to create applications for Microsoft Windows, Windows Mobile, .NET Framework, Silverlight as well as dynamic websites and web applications. Visual Studio is available for Windows and Mac.

Help how to open:

Use Visual Studio and other tools to work with *.def files.

How to convert:

Conversion to other formats is not possible.

List of software applications associated to the .def file extension

Recommended software programs are sorted by OS platform (Windows, macOS, Linux, iOS, Android etc.)
and possible program actions that can be done with the file: like open def file, edit def file, convert def file, view def file, play def file etc. (if exist software for corresponding action in's database).

Click on the tab below to simply browse between the application actions, to quickly get a list of recommended software, which is able to perform the specified software action, such as opening, editing or converting def files.

Software that open def file - Definition data

Programs supporting the exension def on the main platforms Windows, Mac, Linux or mobile. Click on the link to get more information about RAD Studio for open def file action.

Microsoft Windows:

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