Format Command

Examples, options, switches, and more details about formatting

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Updated on December 2, 2020

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The format command is a Command Prompt command used to format a specified partition on a hard drive (internal or external), floppy disk, or flash drive to a specified file system.

You can also format drives without using a command. See How to Format a Hard Drive in Windows for instructions.

Format Command Availability

The format command is available from within the Command Prompt in all Windows operating systems including Windows 11, Windows 10, Windows 8, Windows 7, Windows Vista, Windows XP, and older versions of Windows as well. You need to run an elevated Command Prompt to have the proper permissions.

Screenshot of the format command in Windows 10 Command Prompt — Format Command (Windows 10).

However, it's only useful from within Windows if you're formatting a partition that can be shut down, or in other words, one that isn't currently dealing with locked files (since you can't format files that are in use). See How to Format C if that's what you need to do.

Beginning in Windows Vista, the format command performs a basic write zero hard drive sanitization by assuming the /p:1 option. This isn't the case in Windows XP and earlier versions of Windows.

See How to Wipe a Hard Drive for various ways to completely erase a hard drive, no matter what version of Windows you have. Most data destruction programs let you choose between several data sanitization methods to ensure that the files are securely overwritten and can't be retrieved with data recovery programs.

The format command can also be found in the Command Prompt tool that's available in Advanced Startup Options and System Recovery Options. It's also a DOS command, available in most versions of MS-DOS.

Format Command Syntax

format drive: [/q] [/c] [/x] [/l] [/fs:file-system] [/r:revision] [/d] [/v:label] [/p:count] [/?]

The availability of certain format command switches and other format command syntax may differ from operating system to operating system. See How to Read Command Syntax if you're not sure how to read the format command syntax as it's described on this page.

Format Command Options
Item	Explanation
drive:	This is the letter of the drive/partition that you want to format.
/q	This option will quick format the drive, meaning it will be formatted without a bad sector search. This is not recommend in most situations.
/c	You can enable file and folder compression using this format command option. This is only available when formatting a drive to NTFS.
/x	This format command option will cause the drive to dismount, if it has to, before the format.
/l	This switch, which only works when formatting with NTFS, uses large size file records instead of small size ones. Use /l on dedupe-enabled drives with files greater than 100 GB or risk an ERROR_FILE_SYSTEM_LIMITATION error.
/fs:file-system	This option specifies the file system you want to format the drive: to. Options for file-system include FAT, FAT32, exFAT, NTFS, or UDF.
/r:revision	This option forces the format to a specific version of UDF. Options for revision include 2.50, 2.01, 2.00, 1.50, and 1.02. If no revision is specified, 2.01 is assumed. The /r: switch can only be used when using /fs:udf.
/d	Use this format switch to duplicate metadata. The /d option only works when formatting with UDF v2.50.
/v:label	Use this option with the format command to specify a volume label. If you don't use this option to specify a label, you'll be asked to after the format is complete.
/p:count	This format command option writes zeros to every sector of the drive: once. If you specify a count, a different random number will be written to the entire drive that many times after the zero writing is complete. You can not use the /p option with the /q option. Beginning in Windows Vista, /p is assumed unless you use /q [ KB941961].
/?	Use the help switch with the format command to show detailed help about the command's several options, including ones we did not mention above, like /a, /f, /t, /n, and /s. Executing format /? is the same as using the help command to execute help format.

There are some other less commonly used format command switches, too, like /A:size which lets you choose a custom allocation unit size, /F:size which specifies the size of the floppy disk that's to be formatted, /T:tracks which specifies the number of tracks per disk side, and /N:sectors which specifies the number of sectors per track.

You can output any results of the format command to a file using a redirection operator with the command. See How to Redirect Command Output to a File for help or check out Command Prompt Tricks for even more tips.

Format Command Examples

Here are some examples of how to use the format command:

Quick Format

 format e: /q /fs:exFAT

In the above example, the format command is used to quick format the e: drive to the exFAT file system.

To adopt this above example for yourself, switch out the letter e for whatever your drive's letter is that needs formatted, and change exFAT to be whatever file system you want to format the drive to. Everything else written above should stay the exact same to perform the quick format.

 format g: /q /fs:NTFS

Above is another example of the quick format command to format the g: drive to the NTFS file system.

Format and Write Zeros

 format d: /fs:NTFS /v:Media /p:2

In this example, the d: drive will have zeros written to every sector on the drive twice (because of the "2" after the "/p" switch) during the format, the file system will be set to NTFS, and the volume will be named Media.

Format to Same File System

 format d:

Using the format command without switches, specifying only the drive to be formatted, will format the drive to the same file system it detects on the drive. For example, if it was NTFS before the format, it will remain NTFS.

If the drive is partitioned but not already formatted, the format command will fail and force you to try again, this time specifying a file system with the /fs switch.