How do you format an external hard drive to ext4 via the command line in ubuntu?


1 Answer 1


The command is mkfs.ext4, see its man page.

If you are ok with the default settings(1), it's just

mkfs.ext4 /dev/yourpartitionhere


(1) from the man page:

The defaults of the parameters for the newly created filesystem, if not overridden by the options listed below, are controlled by the /etc/mke2fs.conf configuration file. See the mke2fs.conf(5) manual page for more details.

  • Okay thanks. How do you get the device information? Like the command to know if it is /dev/sda or /dev/sdb? Nov 13, 2014 at 8:03
  • 3
    Never mind i got it..its sudo fdisk -l . Thanks Nov 13, 2014 at 8:22
  • May also need to use fdisk fist to setup the partitions sudo fdisk /dev/sdx -> d -> n -> 1 -> enter -> enter -> w then the above sudo mkfs.ext4 /dev/sdx1 depending on the partitions, it should be /dev/sdx1 most likely it is not /dev/sdx Dec 16, 2018 at 11:20

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