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File Extensions

Browse file extensions by category or letter. Learn what each file type is used for and find software that can open, view, edit, or convert it.

17
Indexed file extensions

Find the right information for any file extension

Use this directory to look up file formats, understand what files are used for, and find compatible applications for Windows, macOS, Linux, mobile, and online tools.

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17 extensions
Letter: I Clear all
.IDX

Index File

The IDX file extension is primarily used to denote an index file, which serves as a pointer or metadata repository for a larger data s…

Data
.IFC

Industry Foundation Classes

The IFC (Industry Foundation Classes) file format is an open, international standard for Building Information Modeling (BIM) data. It…

Data
.IGC

International Gliding Commission Flight Data File

The IGC file format is a standardized data format used primarily in the aviation industry, specifically for gliding, paragliding, and…

Data
.IGES

Initial Graphics Exchange Specification

The IGES (Initial Graphics Exchange Specification) file format is a vendor-neutral file format that allows the digital exchange of inf…

Data
.IGES (.IGS, .IGES)

Initial Graphics Exchange Specification

The IGES (Initial Graphics Exchange Specification) file format is a vendor-neutral file format that allows the digital exchange of inf…

Data
.IGS

Initial Graphics Exchange Specification

The IGES (Initial Graphics Exchange Specification) file format, identified by the .igs extension, is a vendor-neutral file format desi…

Data
.IMG

Disk Image File

An IMG file is a disk image, a single file containing the complete structure and contents of a data storage medium, such as a hard dri…

Data
.IMOVIEPROJ

iMovie Project File

The imovieproj file is a proprietary project file format created and used exclusively by Apple's iMovie video editing software. Unlike…

Video
.IMY

iMelody Ringtone File

The IMY file extension is primarily associated with the iMelody format, a monophonic ringtone format originally developed by Ericsson…

Audio
.INC

Include File

An INC file is a text-based file used across various programming and scripting languages to store reusable code, declarations, constan…

Programming
.INF

Setup Information File

An INF file, short for Setup Information file, is a plain text file format used by Microsoft Windows for installing software and hardw…

Data
.IPA

iOS App Package

The IPA (iOS App Package) file extension is a proprietary archive file format used by Apple's iOS operating system to distribute appli…

Archive
.IPSW

iPhone Software Package

An IPSW file is a proprietary archive format used by Apple to distribute firmware updates for iOS, iPadOS, tvOS, and watchOS devices…

Archive
.IPYNB

Jupyter Notebook

The IPYNB file extension stands for Interactive Python Notebook, which is the standard format used by the Jupyter Notebook application…

Programming
.ISO

International Organization for Standardization (ISO) Disk Image

An ISO file, often referred to as an ISO image, is an archive file that contains an identical copy (or image) of the data found on an…

Archive
.ITMT

iTones Music Theme File

The ITMT file extension is a specialized data format primarily associated with iTones, a legacy software utility designed for the crea…

Data
.IVY

Apache Ivy Module Descriptor

The .ivy file is a configuration file used by Apache Ivy, which is a popular dependency manager for Java-based projects, often integra…

Data
.IDX

Index File

The IDX file extension is primarily used to denote an index file, which serves as a pointer or metadata repository for a larger data set. One of its most commo…

Data
.IFC

Industry Foundation Classes

The IFC (Industry Foundation Classes) file format is an open, international standard for Building Information Modeling (BIM) data. It is developed by buildingS…

Data
.IGC

International Gliding Commission Flight Data File

The IGC file format is a standardized data format used primarily in the aviation industry, specifically for gliding, paragliding, and hang gliding. It was deve…

Data
.IGES

Initial Graphics Exchange Specification

The IGES (Initial Graphics Exchange Specification) file format is a vendor-neutral file format that allows the digital exchange of information among Computer-A…

Data
.IGES (.IGS, .IGES)

Initial Graphics Exchange Specification

The IGES (Initial Graphics Exchange Specification) file format is a vendor-neutral file format that allows the digital exchange of information among Computer-A…

Data
.IGS

Initial Graphics Exchange Specification

The IGES (Initial Graphics Exchange Specification) file format, identified by the .igs extension, is a vendor-neutral file format designed for transferring 2D…

Data
.IMG

Disk Image File

An IMG file is a disk image, a single file containing the complete structure and contents of a data storage medium, such as a hard drive, floppy disk, CD-ROM…

Data
.IMOVIEPROJ

iMovie Project File

The imovieproj file is a proprietary project file format created and used exclusively by Apple's iMovie video editing software. Unlike a finished video file (s…

Video
.IMY

iMelody Ringtone File

The IMY file extension is primarily associated with the iMelody format, a monophonic ringtone format originally developed by Ericsson for use in early mobile p…

Audio
.INC

Include File

An INC file is a text-based file used across various programming and scripting languages to store reusable code, declarations, constants, or configuration sett…

Programming
.INF

Setup Information File

An INF file, short for Setup Information file, is a plain text file format used by Microsoft Windows for installing software and hardware components. It contai…

Data
.IPA

iOS App Package

The IPA (iOS App Package) file extension is a proprietary archive file format used by Apple's iOS operating system to distribute applications. It essentially f…

Archive
.IPSW

iPhone Software Package

An IPSW file is a proprietary archive format used by Apple to distribute firmware updates for iOS, iPadOS, tvOS, and watchOS devices. It contains all the neces…

Archive
.IPYNB

Jupyter Notebook

The IPYNB file extension stands for Interactive Python Notebook, which is the standard format used by the Jupyter Notebook application and its predecessor, IPy…

Programming
.ISO

International Organization for Standardization (ISO) Disk Image

An ISO file, often referred to as an ISO image, is an archive file that contains an identical copy (or image) of the data found on an optical disc, like a CD…

Archive
.ITMT

iTones Music Theme File

The ITMT file extension is a specialized data format primarily associated with iTones, a legacy software utility designed for the creation and management of cu…

Data
.IVY

Apache Ivy Module Descriptor

The .ivy file is a configuration file used by Apache Ivy, which is a popular dependency manager for Java-based projects, often integrated with Apache Ant. The…

Data

Frequently Asked Questions

Everything you need to know about file extensions

You can search by entering a file extension directly in the search bar or browse the directory by category or alphabetical index.

Each listing provides a definition of the file extension, common use cases, compatible software, supported platforms, and related or alternative formats.

The database is updated regularly to reflect new file extensions, changes in software compatibility, and evolving file format standards.