mlabel

Set a volume label on a FAT/VFAT filesystem

$ mlabel -i [/dev/sda] ::"[new_label]"

$ mlabel -s -i [/dev/sda] ::

$ mlabel -c -i [/dev/sda] ::

$ mlabel -n -i [/dev/sda] ::

$ mlabel -N [12345678] -i [/dev/sda] ::

mlabel [-v] [-c] [-s] [-n] [-N serial] drive:[newlabel_]

mlabel adds, displays, or removes volume labels on MS-DOS FAT and VFAT filesystems. When invoked without options, it displays the current label and prompts for a new one.
Volume labels are limited to 11 single-byte characters. The tool validates and adjusts labels to ensure MS-DOS compatibility. An empty label input (pressing return at prompt) deletes the existing label.
mlabel is part of the mtools package, which provides utilities for accessing MS-DOS filesystems from Unix/Linux without mounting.

-c

Clear existing label without prompting

Show existing label without prompting

Assign new random serial number to disk

Set specific serial number; 8-digit hexadecimal, no spaces

Verbose mode; display new label if changed

Specify device directly instead of using drive letter

Labels are limited to 11 characters and must be valid MS-DOS format. Invalid characters are automatically corrected. The serial number is stored in the boot sector and used by Windows for volume identification.

mlabel is part of mtools, originally developed by Emmet P. Gray in the late 1980s. Mtools provides MS-DOS file system utilities for Unix systems, allowing access to FAT filesystems without mounting.

fatlabel(8), mtools(1), mdir(1)