Type: External (1.0 and later)


FORMAT d:[/1][/4][/8][/F:(size)] [/N:(sectors)] [/T:(tracks)] [/B|/S][/C]
[/V:(label)] [/Q][/U][/V]

Purpose: Formats a disk to accept DOS files.


Formats the disk in the specified drive to accept DOS files, analyzing the entire disk for defects.

Initializes the directory and file allocation tables. Can be used to format both diskettes and fixed disks.

In some earlier versions of DOS, the drive designation letter was optional. If you are using one of these versions, you can format a diskette or a FIXED DISK if you enter FORMAT while working in that drive. Format can completely erase the contents of your hard drive.

/1 - Format for single-sided use, regardless of the drive type.

/4 - Formats a double-density diskette in a high-density type disk drive. Files written to a double-sided disk using a high-density drive may not be reliable.

/8 - Formats at 8 sectors per track. If /8 is not specified, FORMAT defaults to 9 or 15 sectors per track, depending upon the disk drive type. The /V option cannot be used with the /8 option.

/F:(size) - Formats disks to specific sizes. You can specify the target disk to be a size value from 160Kb to 2.88Mb. Do not format a floppy disk at a size higher than it was designed for.

/N:(sectors) - Specifies the number of sectors per track on the disk. Used to format a 3.5 inch disk with the number of sectors per track specified using this option. For 720 K-byte disks, this value should be entered as łN:9.˛

/T:(tracks) - Specifies the number of tracks on the disk. Used to format a 3.5 inch disk with the number of tracks specified using this option. For both 720 K-byte disks and 1.44 K-byte disks, this value should be entered as T:80.

/B - Formats a disk reserving room on the disk to later copy the DOS system files.

/S - Copies the operating system files to the disk after formatting. These system files are hidden files and will not appear in a directory listing. Using some versions of DOS, this must be the last option entered.

/C - Causes FORMAT to retest badclusters, otherwise FORMAT will mark the clusters as bad but will not retest them. (In DOS versions before Version 6, FORMAT always retested any bad clusters.)

/V:(label) - Causes FORMAT to prompt for a volume label after the disk is formatted. The label can be of 1 to 11 characters. The same characters acceptable in filenames are acceptable in the volume label (however, you cannot add a filename extension). The /8 option cannot be used with the /V option. DOS Version 5 automatically assigns Label as the disk label and creates a unique serial number in the boot sector of the disk. The serial number is displayed at the end of the formatting process.

/Q - Provides a quick way to format a disk . This option erases the file allocation table and the root directory, but does not identify bad sectors.

/U - Completely erases all data on the target disk making it impossible to perform an UNFORMAT later.

/V - Displays a prompt so that a volume label can be entered.


If you want to format a floppy disk as a double-density disk in a 1.2M drive, you should enter the following:

format a:/4

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