What is the Format Command?
The format command is also a DOS command available in MS-DOS.
Note: You can also format drives without using a command. See How To Format a Hard Drive in Windows for instructions.
Format Command Syntax
format drive: [/q] [/c] [/x] [/fs:file-system] [/r:revision] [/v:label] [/p:count] [/?]
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. I do not recommend doing this 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.
/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.
/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 I did not mention above like /a, /f, /t, /l, /n, /s, and /d. Executing format /? is the same as using the help command to execute help format.
Tip: 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
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.
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 during the format, the file system will be set to NTFS, and the volume will be named Media.
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.
Note: If the drive is partitioned but not already formatted, the format command will fail and force you to try the format again, this time specifying a file system with the /fs switch.
Format Command Availability
Beginning in Windows Vista, the format command performs a basic write zero hard drive sanitization by assuming the /p:1 option when executing the format command. This is not 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.
The format command is also available in MS-DOS.
Note: The availability of certain format command switches and other format command syntax may differ from operating system to operating system.
Format Related Commands
In MS-DOS, the format command is often used after using the fdisk command.
The format command isn't often used in the Command Prompt in Windows.