ABT File

What are ABT files and how to open them

Are you having problems opening an ABT 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 ABT files.

What is an ABT file?

An .ABT file is a Verity Collection Index About file.

Verity Collection Index About files (extension .abt) hold general description data about a Verity Collection, used with Verity indexing/search systems. They provide summary information such as the collection's name, description, creation or modification dates, and metadata needed to understand or display the collection in user interfaces. These .abt files are not for storing the searchable content itself or per-document words; they instead give collection-level context and diagnostics.

The Verity engine writes .abt files within each collection's assists directory. These files are generated automatically when a collection is created or updated. Verity's collection management tools or commands (for example mkvdk) may read them when displaying "about" information for the collection or when administering collections - such as showing when it was last changed or what description it carries.

Technically, .abt files are plain-text structured files. They begin with the ASCII header at offset 0: "$control:1", and contain the literal string "COLLECTION_ABOUT" somewhere inside. These identifiers are used by Verity tools to recognize that a given assists file is the collection about descriptor.

How to open ABT files

Important: Different programs may use files with the ABT file extension for different purposes, so unless you are sure which format your ABT 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 ABT 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 ABT files. Remember, different programs may use ABT 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 ABT file formats, example files, or compatible programs. Please use the links below or email us at submit@file.org to discuss further.