UDF File
Did your computer fail to open an UDF file? We explain what they are used for and recommend software that we know can open or otherwise handle your .UDF files.
What is an UDF file?
An .UDF file is an User Defined Function for Excel file. 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.
Users can access previously saved formulas and functions through these UDF files to use them across multiple spreadsheets without the need to code the functions and formulas again manually. 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 changes the saved formulas and functions of the spreadsheet.
How to open UDF files
You will need a program compatible with the specific file you are trying to open, as different programs may use files with extension UDF for different purposes. We have identified 1 UDF opener for Windows that is compatible with this specific type of UDF file.
Programs that open UDF files
 | Microsoft Excel | Verified |
What else are .UDF files used for?
While User Defined Function for Excel is a popular type of UDF-file, we know of 3 different uses of the .UDF extension.
The UDF file extension indicates to your device which app can open the file. However, different apps may use the same file extension for different types of data. So an UDF opener may not be able to open all kinds of UDF files. In this case, look through all formats to make sure you find the best suited UDF viewer.
Universal Data Format
Through our analysis of UDF files, we know that one use of the format is Universal Data Format. We have not yet described in detail what these files contain and what they are used for, but our team is working tiredlessly through thousands of file formats. We'd love hearing from you if you have information about the format.
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!
X-ray diffraction data file format
Through our analysis of UDF files, we know that one use of the format is X-ray diffraction data file format. We have not yet described in detail what these files contain and what they are used for, but our team is working tiredlessly through thousands of file formats. We'd love hearing from you if you have information about the format.
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!
Various UDF file openers, viewers, etc.
These apps are known to open certain types of UDF files. Remember, different programs may use UDF files for different purposes, so you may need to try out a few of them to be able to open your specific file.
 | IsoBuster | User submitted |
 | PeaZip | User submitted |
 | Bandizip | User submitted |
 | Hamster Lite Archiver | User submitted |
 | Stuffit Expander | User submitted |
 | Hamster Free Archiver | User submitted |
 | Any Video Converter Professional | User submitted |
 | Microsoft Visual Studio .NET | User submitted |
 | Hamster Free ZIP Archiver | User submitted |
 | Flash Movie Player | User submitted |
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