GP4 File

What are GP4 files and how to open them

Are you having problems opening a GP4 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 GP4 files.

What is a GP4 file?

GP4 files have multiple uses, and CCITT Fax Format is one of them. Read more about the other uses further down the page.

CCITT Fax Format

Files that contain the .gp4 file extension are used by a variety of fax software applications. The .gp4 file extension is used to save generic fax image files.

Prior to digital fax software products, users had to have a fax device to send and receive fax messages. Once the Internet evolved, software developers began creating digital fax products, allowing users to send and receive faxes using their computers and an Internet connection.

GP4 files are saved in the CCITT file format. This standardized Group 4 format stores 1-bit or bi-level images using lossless file compression. The GP4 file format is able to compress the fax files into smaller file sizes than older file format versions without losing image quality.

How to open GP4 files

Important: Different programs may use files with the GP4 file extension for different purposes, so unless you are sure which format your GP4 file is, you may need to try a few different programs.

While we have not verified the apps ourselves yet, our users have suggested ten different GP4 openers which you will find listed below.

Last updated: January 22, 2025

All known file formats using extension .GP4

While CCITT Fax Format is a popular type of GP4-file, we know of 3 different uses of the .GP4 file extension. Different software may use files with the same extension for different types of data.

Guitar Pro v4 Tablature

Guitar Pro 4 allows for the editing of guitar and bass tablature files and the creation of scores for stringed instruments, such as the bass and the guitar. The music files created and saved by the Guitar Pro 4 software are saved with the .gp4 file extension. Guitar Pro 3 used file extension gp3.

While the files contain scores used to create music, the files do not have any actual audio data in and of themselves.

GP4 opener for Windows

We have identified 2 GP4 openers that are compatible with this specific type of GP4 file.

GreenPAK Designer Project

We know that one GP4 format is GreenPAK Designer Project. We have not yet analyzed in detail what these files contain and what they are used for. We're working on it.

Various apps that use files with this extension

These apps are known to open certain types of GP4 files. Remember, different programs may use GP4 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 GP4 file formats, example files, or compatible programs. Please use the links below or email us at submit@file.org to discuss further.