A file viewer is a utility

application software Application software is any computer program that is intended for end-user use not operating, administering or programming the computer. An application (app, application program, software application) is any program that can be categorized as ...

on operating systems, such as

Linux Linux ( ) is a family of open source Unix-like operating systems based on the Linux kernel, an kernel (operating system), operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically package manager, pac ...

macOS macOS, previously OS X and originally Mac OS X, is a Unix, Unix-based operating system developed and marketed by Apple Inc., Apple since 2001. It is the current operating system for Apple's Mac (computer), Mac computers. With ...

, or

Windows Windows is a Product lining, product line of Proprietary software, proprietary graphical user interface, graphical operating systems developed and marketed by Microsoft. It is grouped into families and subfamilies that cater to particular sec ...

. The file viewer is responsible for user access of files located on a

data storage device Data ( , ) are a collection of discrete or continuous values that convey information, describing the quantity, quality, fact, statistics, other basic units of meaning, or simply sequences of symbols that may be further interpreted form ...

. File viewers allow the user to open and view content on a device, such as a

Personal Computer A personal computer, commonly referred to as PC or computer, is a computer designed for individual use. It is typically used for tasks such as Word processor, word processing, web browser, internet browsing, email, multimedia playback, and PC ...

(PC) or a

mobile phone A mobile phone or cell phone is a portable telephone that allows users to make and receive calls over a radio frequency link while moving within a designated telephone service area, unlike fixed-location phones ( landline phones). This rad ...

Overview

File viewer applications can be categorized based on their functionality: * File Viewer Only applications do not allow the user to edit files. * File Viewer and Converter applications allow viewing data, exporting data in a different

file format A file format is a Computer standard, standard way that information is encoded for storage in a computer file. It specifies how bits are used to encode information in a digital storage medium. File formats may be either proprietary format, pr ...

, and copying information to the clipboard. * File Viewer and Editor applications allow the user to view existing files, modify an existing file's content, or create a new file of a specific type. Differences in functionality are often due to software licensing and proprietary file formats. Some formats can be freely viewed but require specific software for creation or modification. For example, .DBF files created in

dBASE dBase (also stylized dBASE) was one of the first database management systems for microcomputers and the most successful in its day. The dBase system included the core database engine, a query system, a Form (programming), forms engine, and a pr ...

could be viewed in

Norton Commander Norton Commander (NC) is a discontinued prototypical orthodox file manager (OFM), written by John Socha and released by Peter Norton Computing (later acquired in 1990 by the NortonLifeLock, Symantec corporation). NC provides a text-based user i ...

, while .PDF files require software like

Adobe Photoshop Adobe Photoshop is a raster graphics editor developed and published by Adobe Inc., Adobe for Microsoft Windows, Windows and macOS. It was created in 1987 by Thomas Knoll, Thomas and John Knoll. It is the most used tool for professional digital ...

LibreOffice LibreOffice () is a free and open-source office productivity software suite developed by The Document Foundation (TDF). It was created in 2010 as a fork of OpenOffice.org, itself a successor to StarOffice. The suite includes applications ...

, or

Microsoft Word Microsoft Word is a word processor program, word processing program developed by Microsoft. It was first released on October 25, 1983, under the name Multi-Tool Word for Xenix systems. Subsequent versions were later written for several other platf ...

for editing, whereas

Acrobat Reader Adobe Acrobat is a family of application software and web services developed by Adobe Inc. to view, create, manipulate, print and manage Portable Document Format (PDF) files. The family comprises Acrobat Reader (formerly Reader), Acrobat (former ...

supports only viewing. To function correctly, a file viewer must interpret the structural information of a file format, such as

byte order '' Jonathan_Swift.html" ;"title="Gulliver's Travels'' by Jonathan Swift">Gulliver's Travels'' by Jonathan Swift, the novel from which the term was coined In computing, endianness is the order in which bytes within a word (data type), word of d ...

, character encoding, and

newline A newline (frequently called line ending, end of line (EOL), next line (NEL) or line break) is a control character or sequence of control characters in character encoding specifications such as ASCII, EBCDIC, Unicode, etc. This character, or ...

styles. Media file viewers, such as video players, often rely on

codecs A codec is a computer hardware or software component that encodes or decodes a data stream or signal. ''Codec'' is a portmanteau of coder/decoder. In electronic communications, an endec is a device that acts as both an encoder and a decoder o ...

rather than built-in format support. This approach allows users to extend a media viewer’s compatibility with additional file types. Some editors, such as Audacity, allow users to open files as raw data, a feature sometimes used in glitch art. Additionally, some file viewers act as filters that convert binary files into text (e.g., antiword), though this may result in data loss. Image viewers display graphic files on screen. Some viewers, such as IrfanView, can read multiple graphic file formats, while others, such as JPEGview only support a single format. Common image viewer features include

thumbnail Thumbnails are reduced-size versions of pictures or videos, used to help in recognizing and organizing them, serving the same role for images as a normal text index does for words. In the age of digital images, visual search engines and image-o ...

preview and creation, image zooming and rotation, color balance and gamma correction, resizing, etc. A

web browser A web browser, often shortened to browser, is an application for accessing websites. When a user requests a web page from a particular website, the browser retrieves its files from a web server and then displays the page on the user's scr ...

functions as a file viewer for

HTML Hypertext Markup Language (HTML) is the standard markup language for documents designed to be displayed in a web browser. It defines the content and structure of web content. It is often assisted by technologies such as Cascading Style Sheets ( ...

and various other file types. While HTML files are stored as plain text, web browsers render them into a structured, human-readable format. Additionally, web browsers can display

multimedia Multimedia is a form of communication that uses a combination of different content forms, such as Text (literary theory), writing, Sound, audio, images, animations, or video, into a single presentation. T ...

files, including images, videos, preformatted documents, and interactive content such as 3D models,

augmented reality Augmented reality (AR), also known as mixed reality (MR), is a technology that overlays real-time 3D computer graphics, 3D-rendered computer graphics onto a portion of the real world through a display, such as a handheld device or head-mounted ...

and

virtual reality Virtual reality (VR) is a Simulation, simulated experience that employs 3D near-eye displays and pose tracking to give the user an immersive feel of a virtual world. Applications of virtual reality include entertainment (particularly video gam ...

elements.

Examples of File Viewers

Plain text files

Less (Unix) less is a terminal pager Computer program, program on Unix, Microsoft Windows, Windows, and Unix-like systems used to view (but not change) the contents of a text file one screen at a time. It is similar to , but has the extended capability of al ...

* gedit (Unix) *

Most (Unix) most is a terminal pager program on Unix, OpenVMS, MS-DOS, Windows and Unix-like systems used to view (but not change) the contents of a text file one screen at a time. Programs of this sort are called ''pagers''. It is similar to more, but ha ...

pg (Unix) pg is a terminal pager program on Unix and Unix-like systems for viewing text files. It can also be used to page through the output of a command via a pipe. pg uses an interface similar to vi, but commands are different. As of 2018, pg has ...

More (command) In computing, more is a command to view (but not modify) the contents of a text file one screen at a time. It is available on Unix and Unix-like systems, DOS, Digital Research FlexOS, IBM/Toshiba 4690 OS, IBM OS/2, Microsoft Windows and ReactOS. ...

* vi *

notepad A notebook (also known as a notepad, writing pad, drawing pad, or legal pad) is a book or stack of paper pages that are often Ruled paper, ruled and used for purposes such as note-taking, Diary, journaling or other writing, drawing, or scrapbooki ...

Microsoft Office documents

Microsoft Word Viewer Microsoft Word Viewer is a discontinued freeware program for Microsoft Windows that can display and print Microsoft Word documents. Word Viewer allows text from a Word document to be copied into clipboard and pasted into a word processor. The l ...

* Microsoft Excel Viewer * PowerPoint Viewer

PDF files

Adobe Acrobat Adobe Acrobat is a family of application software and web services developed by Adobe Inc. to view, create, manipulate, print and manage Portable Document Format (PDF) files. The family comprises Acrobat Reader (formerly Reader), Acrobat (former ...

* Atril *

Evince Evince (), also known as GNOME Document Viewer, is a Free and open-source software, free and open-source document viewer supporting many document file formats including Portable Document Format, PDF, PostScript, DjVu, Tagged Image File Format ...

* PDF.js *see :PDF readers

Image files

* Directory Opus * IrfanView * ACDSee *

XnView XnView is an image organizer and general-purpose file manager used for viewing, converting, organizing and editing raster images, as well as general purpose file management. It comes with built-in hex inspection, batch renaming, image scan ...

Video and audio files

* Media Player Classic *

Windows Media Player Windows Media Player (WMP, officially referred to as Windows Media Player Legacy to retronym, distinguish it from Windows Media Player (2022), the new Windows Media Player introduced with Windows 11) is the first media player (application soft ...

* VLC

Binary files

* Hiew * UltraEdit * Midnight Commander * ExifTool

Programming languages source code files

Notepad++ Notepad++ (sometimes npp or NPP) is a text and source code editor for use with Microsoft Windows. It supports tabbed editing, which allows working with multiple open files in one window. The program's name comes from the C postfix increment op ...

VS Code Visual Studio Code, commonly referred to as VS Code, is an integrated development environment developed by Microsoft for Windows, Linux, macOS and web browsers. Features include support for debugging, syntax highlighting, intelligent code comple ...

VRML and 3D models files

* VRML Viewer * FreeWRL * view3dscene * Microsoft 3D viewer

Microsoft Project plan files

* Microsoft Project * Seavus Project Viewer (software)

References

{{GUI widgets File managers Graphical user interfaces