Opening UDF files

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

What is an UDF file?

The .udf file extension is used for a program configuration file format that was developed by Microsoft. Also known as user defined function files, these UDF files are generated by Microsoft Excel when users create custom formulas for their spreadsheet documents.Microsoft Excel provides VBA (Visual Basic for Applications) support. This allows users to develop custom functions and formulas for their spreadsheets, which are stored in a UDF file.Users can access previously saved formulas and functions through these UDF files, in order to use it across multiple spreadsheets without the need to manually code the functions and formulas again. The content of a .udf file is used by Microsoft Excel whenever a user opens and edits a spreadsheet with custom functions and formulas that have been saved in the UDF file. The data in a .udf file is also updated by Microsoft Excel when the user makes changes to the saved formulas and functions of the spreadsheet.