A chi file extension is associated with the Microsoft Help and used index files.

There are 4 other file types using
the CHI file extension!

empty icon.chi - ChiWriter document file

empty icon.chi - TOMBO encrypted data

empty icon.chi - Chinese localization language

empty icon.chi - CUHP input data

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CHI file extension - Microsoft Help file index

What is chi file? How to open chi files?

File type specification:

Various data file type icon Various data file type

The chi file extension is related to the Microsoft Help file index files.

Index file used when you ship chm files that are likely to remain on a CD-ROM, as in the case of the MSDN Library.

The chi file allows certain navigation information to be installed locally on a hard disk for quick access, while the main content lives on the CD-ROM.

A chi file should not be used in a non-CD-ROM scenario. When a chi file is not used, all the information that would be in it remains in the chm itself.

Microsoft Compiled HTML Help is a proprietary format for online help files, developed by Microsoft and first released in 1997 as a successor to the Microsoft WinHelp format.

It was first introduced with the release of Windows 98, and is still supported and distributed through Windows XP, Vista and Windows 7 platforms.

The default software associated to open chi file:

Microsoft Windows Help icon

Microsoft Corporation logoMicrosoft Windows Help  Microsoft Windows software

Company or developer:
Microsoft Corporation

Microsoft Windows Help is used to create help files for Microsoft Windows operating system and other Microsoft applications. Windows Help SDKs are different for every version of Windows it can be called Windows Help, Help and Support Center, Assistance Platform 1.0 Client - Windows Vista Help SDK, Microsoft Windows: HTML Help 1.4 etc.

Microsoft Windows icon

Microsoft Corporation logoMicrosoft Windows  Microsoft Windows software

Company or developer:
Microsoft Corporation

A family of operating systems developed by the Microsoft Corp. The first Windows was released in 1985 as a GUI add-on to MS-DOS. MS-DOS based Windows versions were developed to 2000, when was released the last version called Windows ME. Windows based on NT core started in 1993. Windows NT family are developed to these days, the latest version is called Microsoft Windows 11.

Visual FoxPro icon

Microsoft Corporation logoVisual FoxPro  Microsoft Windows software

Company or developer:
Microsoft Corporation

Microsoft Visual FoxPro is set of tools that is used to create database applications, desktop applications and web applications. Visual FoxPro uses own proprietary data centric object oriented and procedural programming language. Visual FoxPro is available for Microsoft Windows.

Help how to open:

This file type is not meant to be opened directly, there is no software that could open and work with it directly, or there is no information available in public sources about opening this file type. This is usually the case of some internal data files, caches, temporary files etc.

How to convert:

As far as we know, this .chi file type can't be converted to any other file format. This is usually the case of system, configuration, temporary, or data files containing data exclusive to only one software and used for its own purposes. Also some proprietary or closed file formats cannot be converted to more common file types in order to protect the intellectual property of the developer, which is for example the case of some DRM-protected multimedia files.

List of software applications associated to the .chi file extension

Recommended software programs are sorted by OS platform (Windows, macOS, Linux, iOS, Android etc.)
and possible program actions that can be done with the file: like open chi file, edit chi file, convert chi file, view chi file, play chi file etc. (if exist software for corresponding action in File-Extensions.org's database).

Click on the tab below to simply browse between the application actions, to quickly get a list of recommended software, which is able to perform the specified software action, such as opening, editing or converting chi files.

Programs that can create chi file - Microsoft Help file index

Programs supporting the exension chi on the main platforms Windows, Mac, Linux or mobile. Click on the link to get more information about Microsoft Windows Help for create chi file action.

Microsoft Windows:

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