FDF File

What are FDF files and how to open them

Are you having problems opening a FDF file or are you simply curious about its contents? We're here to explain the properties of these files and provide you with software that can open or handle your FDF files.

What is a FDF file?

FDF files have multiple uses, and Acrobat Forms Data Format Document is one of them. Read more about the other uses further down the page.

Acrobat Forms Data Format Document

The .fdf file extension refers to a specific document file related to Adobe. FDF files are document files that can be opened or created using Adobe Acrobat reader. FDF means "forms data format". It is a form format specifically for .pdf files.

FDF files are fairly smaller than .pdf files because they mainly contain the form's field data and not the entire form. In other words, .fdf files only have the "contents" of the .pdf without the complete package. Some editorial managers in browsers use files with the .fdf extension to ensure that the file opens in Adobe Reader and not within the browser.

FDF file format is now popularly used as an attachment in spam messages. If you receive an attachment in your email and the size is relatively small, opening it is not advisable and is considered impractical. Large .fdf files should be virus-scanned first before opening them. You may resume downloading the .fdf file once you're done with the necessary security check. Converting the FDF file to PDF is also recommended to make the file more accessible.

How to open FDF files

We have identified two FDF openers that are compatible with this specific type of FDF file.

Programs that open Acrobat Forms Data Format Document files

Last updated: January 22, 2025

All known file formats using extension .FDF

While Acrobat Forms Data Format Document is a popular type of FDF-file, we know of 4 different uses of the .FDF file extension. Different software may use files with the same extension for different types of data.

Floppy Disk File Image

We know that one FDF format is Floppy Disk File Image. We have not yet analyzed in detail what these files contain and what they are used for. We're working on it.

While we have not verified the apps ourselves yet, our users have suggested ten different FDF openers which you will find listed below.

Origin Fitting Function Definition File

We know that one FDF format is Origin Fitting Function Definition File. We have not yet analyzed in detail what these files contain and what they are used for. We're working on it.

SEU Format Definition File

Used with Lattice Source Entry Utility, a tool used for creating role-playing games.

Various apps that use files with this extension

These apps are known to open certain types of FDF files. Remember, different programs may use FDF files for different purposes, so you may need to try out a few of them to be able to open your specific file.

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 FDF file formats, example files, or compatible programs. Please use the links below or email us at submit@file.org to discuss further.