fdisk

Updated

July 31, 2026

Overview

fdisk manipulates DOS/MBR and GPT partition tables on block devices. Interactive by default. For scripting GPT, many prefer parted or sfdisk.

Syntax

sudo fdisk [-l] [device...]
sudo fdisk device          # interactive

Common Options

Option Description
-l List partitions
-x Extra list detail
-w always\|never Wipe signatures when writing (newer)

Interactive keys (common): m help, p print, n new, d delete, t type, w write, q quit.

Safety

Writing a partition table can destroy data. Double-check device (lsblk, fdisk -l). Do not change mounted system disks without a recovery plan.

Examples with Explanations

List all

sudo fdisk -l
sudo fdisk -l /dev/sdb

Interactive create (sketch)

sudo fdisk /dev/sdb
# g  (new GPT)
# n  (new partition — accept defaults or set size)
# t  (type, e.g. 20 Linux filesystem / 31 Linux LVM)
# p  (review)
# w  (write)

Kernel re-read

sudo partprobe /dev/sdb
# or: sudo blockdev --rereadpt /dev/sdb
lsblk /dev/sdb

Scripted dump/restore (sfdisk)

sudo sfdisk -d /dev/sdb > sdb.layout
# sudo sfdisk /dev/sdb < sdb.layout

Notes

  • After partitioning: mkfs, then mount or LVM.
  • NVMe devices: /dev/nvme0n1, partitions /dev/nvme0n1p1.
  • Alignment is usually automatic on modern fdisk.