Formatting disks in Linux command line

Commands necessary to delete partitions, wipe a disk completely and install a new filesystem.

For more details see this answer on AskUbuntu by Mateen Ulhaq

List mounted disks

lsblk

NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINTS
sda      8:0    0 111.8G  0 disk
├─sda1   8:1    0   512M  0 part /boot/efi
├─sda2   8:2    0 110.3G  0 part /
└─sda3   8:3    0   976M  0 part [SWAP]
sdb      8:16   1   7.2G  0 disk
└─sdb1   8:17   1   7.2G  0 part

Unmount the disk to re-format

sudo umount /dev/sdb

Use fdisk utility

sudo fdisk /dev/sdb

Commands to use

  p         # List partitions
  d         # Delete partition
  # repeat p to list d to delete multiple partitions
  n         # Create new partition. Physical, accept defaults for size, etc.
  t         # Change type - for USB drives use option b (vfat) or c (bigger USB sticks)
  w         # Write changes & quit fdisk

Disk is now formatted with one new VFat partition. Now create filesystem:

sudo mkfs -t vfat /dev/sdb1

All fdisk commands

  GPT
   M   enter protective/hybrid MBR

  Generic
   d   delete a partition
   F   list free unpartitioned space
   l   list known partition types
   n   add a new partition
   p   print the partition table
   t   change a partition type
   v   verify the partition table
   i   print information about a partition

  Misc
   m   print this menu
   x   extra functionality (experts only)

  Script
   I   load disk layout from sfdisk script file
   O   dump disk layout to sfdisk script file

  Save & Exit
   w   write table to disk and exit
   q   quit without saving changes

  Create a new label
   g   create a new empty GPT partition table
   G   create a new empty SGI (IRIX) partition table
   o   create a new empty MBR (DOS) partition table
   s   create a new empty Sun partition table