A2P File

What are A2P files and how to open them

Are you having problems opening an A2P 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 A2P files.

What is an A2P file?

An .A2P file is an Adlib Tracker II Pattern file.

An Adlib Tracker II Pattern file is a musical data file used by the Adlib Tracker II (AT2) program to store a single pattern of a song. A pattern in AT2 is a block of rows and tracks that defines note events, instruments, effects, and other performance data. The designer uses pattern files to build full songs by arranging many patterns in order.

Files with the .A2P extension are written by Adlib Tracker II when saving an individual pattern. Each such file holds the layout of multiple tracks (channels), the events in those tracks (notes, instrument numbers, effect commands), and pattern metadata such as pattern number and supported features. These files are useful when composing: patterns are edited individually, saved as .A2P, and later loaded into song modules (order lists) or combined into more complete tracks like A2M or A2T modules.

Internal identification of a valid file in this format is achieved through a signature at the very start: the ASCII string a2pattern appears at offset 0 of the file.

How to open A2P files

Important: Different programs may use files with the A2P file extension for different purposes, so unless you are sure which format your A2P file is, you may need to try a few different programs.

While we have not verified the app ourselves yet, our users have suggested a single A2P opener which you will find listed below.

Last updated: August 16, 2026

Various apps that use files with this extension

These apps are known to open certain types of A2P files. Remember, different programs may use A2P files for different purposes, so you may need to try out a few of them to be able to open your specific file.

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File.org helps thousands of users every day, and we would love to hear from you if you have additional information about A2P file formats, example files, or compatible programs. Please use the links below or email us at submit@file.org to discuss further.