fdisk is a

command-line utility A console application or command-line program is a computer program (applications or utilities) designed to be used via a text-only user interface. A console application can be used with a computer terminal, a system console, or a terminal emu ...

for

disk partitioning Disk partitioning or disk slicing is the creation of one or more regions on secondary storage, so that each region can be managed separately. These regions are called partitions. It is typically the first step of preparing a newly installed disk ...

. It has been part of

DOS DOS (, ) is a family of disk-based operating systems for IBM PC compatible computers. The DOS family primarily consists of IBM PC DOS and a rebranded version, Microsoft's MS-DOS, both of which were introduced in 1981. Later compatible syste ...

, DR

FlexOS FlexOS is a discontinued modular real-time multiuser multitasking operating system ( RTOS) designed for computer-integrated manufacturing, laboratory, retail and financial markets. Developed by Digital Research's Flexible Automation Business ...

IBM International Business Machines Corporation (using the trademark IBM), nicknamed Big Blue, is an American Multinational corporation, multinational technology company headquartered in Armonk, New York, and present in over 175 countries. It is ...

OS/2 OS/2 is a Proprietary software, proprietary computer operating system for x86 and PowerPC based personal computers. It was created and initially developed jointly by IBM and Microsoft, under the leadership of IBM software designer Ed Iacobucci, ...

, and early versions of

Microsoft 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 ...

, as well as certain ports of

FreeBSD FreeBSD is a free-software Unix-like operating system descended from the Berkeley Software Distribution (BSD). The first version was released in 1993 developed from 386BSD, one of the first fully functional and free Unix clones on affordable ...

NetBSD NetBSD is a free and open-source Unix-like operating system based on the Berkeley Software Distribution (BSD). It was the first open-source BSD descendant officially released after 386BSD was fork (software development), forked. It continues to ...

OpenBSD OpenBSD is a security-focused operating system, security-focused, free software, Unix-like operating system based on the Berkeley Software Distribution (BSD). Theo de Raadt created OpenBSD in 1995 by fork (software development), forking NetBSD ...

DragonFly BSD DragonFly BSD is a free and open-source Unix-like operating system forked from FreeBSD 4.8. Matthew Dillon, an Amiga developer in the late 1980s and early 1990s and FreeBSD developer between 1994 and 2003, began working on DragonFly BSD in ...

and

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 ...

for compatibility reasons.

Windows 2000 Windows 2000 is a major release of the Windows NT operating system developed by Microsoft, targeting the server and business markets. It is the direct successor to Windows NT 4.0, and was Software release life cycle#Release to manufacturing (RT ...

and its successors have replaced fdisk with a more advanced tool called

diskpart In computing, diskpart is a command-line interface, command-line disk partitioning utility included in Windows 2000 and later Microsoft operating systems, replacing its predecessor, fdisk. The command is also available in ReactOS. Overview T ...

Implementations

DOS

introduced the first version of fdisk (officially dubbed "Fixed Disk Setup Program") in March 1983, with the release of the IBM PC/XT computer (the first PC to store data on a

hard disk A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating hard disk drive platter, pla ...

) and the

IBM PC DOS IBM PC DOS (an acronym for IBM Personal Computer Disk Operating System),Formally known as "The IBM Personal Computer DOS" from versions 1.0 through 3.30, as reported in those versions' respective COMMAND.COM outputs also known as PC DOS or IBM ...

2.0 operating system. fdisk version 1.0 can create one

FAT12 File Allocation Table (FAT) is a file system developed for personal computers and was the default file system for the MS-DOS and Windows 9x operating systems. Originally developed in 1977 for use on floppy disks, it was adapted for use on ...

partition, delete it, change the active partition, or display partition data. fdisk writes the

master boot record A master boot record (MBR) is a type of boot sector in the first block of disk partitioning, partitioned computer mass storage devices like fixed disks or removable drives intended for use with IBM PC-compatible systems and beyond. The concept ...

, which supports up to four partitions. The other three were intended for other operating systems such as

CP/M-86 CP/M-86 is a discontinued version of the CP/M operating system that Digital Research (DR) made for the Intel 8086 and Intel 8088. The system commands are the same as in CP/M-80. Executable files used the relocatable .CMD file format. Digital Re ...

and

Xenix Xenix is a discontinued Unix operating system for various microcomputer platforms, licensed by Microsoft from AT&T Corporation. The first version was released in 1980, and Xenix was the most common Unix variant during the mid- to late-1980s. T ...

, which were expected to have their own partitioning utilities. Microsoft first added fdisk to

MS-DOS MS-DOS ( ; acronym for Microsoft Disk Operating System, also known as Microsoft DOS) is an operating system for x86-based personal computers mostly developed by Microsoft. Collectively, MS-DOS, its rebranding as IBM PC DOS, and a few op ...

in version 3.2. MS-DOS versions 2.0 through 3.10 included OEM-specific partitioning tools, which may have been named fdisk. PC DOS 3.0, released in August 1984, added support for

FAT16 File Allocation Table (FAT) is a file system developed for personal computers and was the default file system for the MS-DOS and Windows 9x operating systems. Originally developed in 1977 for use on floppy disks, it was adapted for use on Ha ...

partitions to handle larger hard disks more efficiently. PC DOS 3.30, released in April 1987, added support for extended partitions. (These partitions do not store data directly but can contain up to 23

logical drive In computer data storage, a volume or logical drive is a single accessible storage area with a single file system, typically (though not necessarily) resident on a single partition of a hard disk. Although a volume might be different from a phys ...

s.) In both cases, fdisk was modified to work with FAT16 and extended partitions. Support for FAT16B was first added to Compaq's fdisk in MS-DOS 3.31. FAT16B later became available with MS-DOS and PC DOS 4.0. The undocumented /mbr switch in fdisk, which could repair the

, soon became popular. IBM PC DOS 7.10 shipped with the new fdisk32 utility.

ROM-DOS Datalight was a privately held software company specializing in power failsafe and high performance software for preserving data integrity in embedded systems. The company was founded in 1983 by Roy Sherrill, and its headquarters is in Bothell, ...

, DR DOS 6.0DR DOS 6.0 User Guide Optimisation and Configuration Tips
/ref>

PTS-DOS PTS-DOS (aka PTS/DOS) is a disk operating system, a DOS clone, developed in Russia by PhysTechSoft and Paragon Technology Systems. History and versions PhysTechSoft was formed in 1991 in Moscow, Russia by graduates and members of MIPT, inf ...

2000 Pro, and

FreeDOS FreeDOS (formerly PD-DOS) is a free software operating system for IBM PC compatible computers. It intends to provide a complete MS-DOS-compatible environment for running Legacy system, legacy software and supporting embedded systems. FreeDOS ca ...

, include an implementation of the fdisk command.

Windows

Windows 95 Windows 95 is a consumer-oriented operating system developed by Microsoft and the first of its Windows 9x family of operating systems, released to manufacturing on July 14, 1995, and generally to retail on August 24, 1995. Windows 95 merged ...

Windows 98 Windows 98 is a consumer-oriented operating system developed by Microsoft as part of its Windows 9x family of Microsoft Windows operating systems. It was the second operating system in the 9x line, as the successor to Windows 95. It was Software ...

, and

Windows ME Windows Me (Millennium Edition) is an operating system developed by Microsoft as part of its Windows 9x family of Microsoft Windows operating systems. It was the successor to Windows 98, and was released to manufacturing on June 19, 2000, and t ...

shipped with a derivative of the MS-DOS fdisk.

and its successors, however, came with the more advanced

and the graphical Disk Management utilities. Starting with Windows 95 OSR2, fdisk supports the

FAT32 File Allocation Table (FAT) is a file system developed for personal computers and was the default file system for the MS-DOS and Windows 9x operating systems. Originally developed in 1977 for use on floppy disks, it was adapted for use on ...

file system. The version of fdisk that ships with Windows 95 does not report the correct size of a hard disk that is larger than 64 GB. An updated fdisk is available from Microsoft to correct this issue. In addition, fdisk cannot create partitions larger than 512 GB, even though FAT32 supports partitions as big as 2 TB. This limitation applies to all versions of fdisk supplied with Windows 95 OSR 2.1, Windows 98 and Windows ME.

IBM OS/2

Before version 4.0,

shipped with two partition table managers. These were the

text mode Text mode is a computer display mode in which content is internally represented on a computer screen in terms of characters rather than individual pixels. Typically, the screen consists of a uniform rectangular grid of ''character cells'', ea ...

fdisk and the graphical fdiskpm. The two have identical functionality, and can manipulate both FAT partitions and the more advanced HPFS partitions. OS/2 4.5 and higher (including

eComStation eComStation or eCS is an operating system based on OS/2 Warp for the 32-bit x86 architecture. It was originally developed by Serenity Systems and Mensys BV under license from IBM. It includes additional applications, and support for new hardwa ...

and

ArcaOS ArcaOS is a Proprietary software, proprietary operating system based on OS/2, developed and marketed by Arca Noae, LLC under license from IBM. It was first released in 2017 and builds on OS/2 Warp 4.52 by adding support for new hardware, fixing ...

) can use the JFS file system, as well as FAT and HPFS. They replaced fdisk with the Logical Volume Manager (LVM).

Mach and 386BSD

fdisk for Mach Operating System was written by Robert Baron. It was ported to

386BSD 386BSD (also known as "Jolix") is a Unix-like operating system that was developed by couple Lynne and William "Bill" Jolitz. Released as free and open source in 1992, it was the first fully operational Unix built to run on IBM PC-compatible s ...

by Julian Elischer, and the implementation is being used by

, *

and

, * all as of 2019, as well as the early versions of

between 1995 and 1997 before OpenBSD 2.2. Tobias Weingartner re-wrote fdisk in 1997 before OpenBSD 2.2, * which has subsequently been forked by

Apple Computer, Inc Apple Inc. is an American multinational corporation and technology company headquartered in Cupertino, California, in Silicon Valley. It is best known for its consumer electronics, software, and services. Founded in 1976 as Apple Computer Com ...

in 2002, and is still used as the basis for fdisk on macOS as of 2019. For native partitions, BSD systems traditionally use BSD disklabel, and fdisk partitioning is supported only on certain architectures (for compatibility reasons) and only in addition to the BSD disklabel (which is mandatory).

Linux

In Linux, fdisk is a part of a standard package distributed by the Linux Kernel organization,

util-linux is a package of utilities distributed by the Linux Kernel Organization for use in a Linux operating system. A fork, (with meaning "next generation"), was created when development stalled, but has been renamed back to , and is the official ve ...

. The original program was written by Andries E. Brouwer and A. V. Le Blanc and was later rewritten by Karel Zak and Davidlohr Bueso when they forked the util-linux package in 2006. An alternative, ncurses-based program,

cfdisk cfdisk is a Linux partition editor, similar to fdisk, but with a different, curses (programming library), curses-based user interface. It is part of the util-linux package of Linux utility programs. The current cfdisk implementation utilizes th ...

, allows users to create partition layouts via a

text-based user interface In computing, text-based user interfaces (TUI) (alternately terminal user interfaces, to reflect a dependence upon the properties of computer terminals and not just text), is a retronym describing a type of user interface (UI) common as an ear ...

(TUI).

References

External links

Linux Partition HOWTO. Partitioning with fdisk

fdisk from utils-linux-ng

blkid - command-line utility to locate/print block device attributes

.
FreeBSD System Manager's Manual, FDISK(8)
{{Windows commands External DOS commands OS/2 commands Unix file system-related software Windows administration Disk partitioning software