How to Check Disk Space on Linux

Running low on disk space wondering how much disk space you have left on your Linux system? Whether you’re a Linux beginner or a seasoned pro, it’s important to understand how to manage your system’s storage effectively. Linux provides several simple commands to give you an overview of disk usage.

we’ll show you easy ways to check how much space is being used, how much is free, and how to identify large files or directories that might be eating up your storage. With these tools at your disposal, you can easily monitor your system and avoid running into space-related issues.

Below are the most commonly used methods:

1. Using df (Disk Free)

The df command shows the disk space usage of all mounted filesystems.

admin@atbytes:~$ df -h

• -h: Displays sizes in human-readable format (e.g., KB, MB, GB).
• Output includes:
• Filesystem: The partition or disk.
• Size: Total disk space.
• Used: Space used.
• Available: Free space.
• Use%: Percentage of space used.
• Mounted on: The mount point.

To check a specific filesystem or directory:

admin@atbytes:~$ df -h /path/to/directory

This will show something like:

Filesystem      Size  Used Avail Use% Mounted on
/dev/sda1        50G   20G   30G  40% /
/dev/sdb1        200G  150G  50G  75% /home

• Size: The total size of the disk.
• Used: How much space is currently used.
• Avail: How much space is still available.
• Use%: The percentage of space used.
• Mounted on: Where the disk is mounted (usually / for the root filesystem, and /home for your personal files).

2. Using du (Disk Usage)

The du command shows the disk usage of files and directories.

admin@atbytes:~$ du -sh /path/to/directory

• -s: Summarizes the total usage of the directory.
• -h: Displays sizes in human-readable format.

Example:-

admin@atbytes:~$ du -sh ~/Documents

You’ll see something like this:

2.3G    /home/username/Documents

This means your Documents folder is using 2.3GB of space.

To check disk usage for all files and subdirectories within a directory:

admin@atbytes:~$du -h /path/to/directory

3. Using lsblk (List Block Devices)

The lsblk command lists information about block devices (disks and partitions), including their size and mount points.

admin@atbytes:~$ lsblk

• Output includes:
• NAME: Device name.
• SIZE: Total size of the device.
• MOUNTPOINT: Where the device is mounted.

Example:

admin@atbytes:~$ lsblk

Output:

NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda      8:0    0    50G  0 disk
├─sda1   8:1    0    40G  0 part /
└─sda2   8:2    0    10G  0 part /home
sdb      8:16   0   100G  0 disk
└─sdb1   8:17   0   100G  0 part /mnt/data

• Explanation:
  • sda is a 50GB disk with two partitions:
    • sda1 (40GB) is mounted as /.
    • sda2 (10GB) is mounted as /home.
  • sdb is a 100GB disk with one partition (sdb1) mounted at /mnt/data.

4. Using fdisk (Partition Table Manipulator)

The fdisk command can display disk partition information.

admin@atbytes:~$ sudo fdisk -l

• -l: Lists partition tables for all disks.
• Requires sudo privileges.

5. Using ncdu (NCurses Disk Usage)

ncdu is an interactive tool for analyzing disk usage.

1. Install ncdu (if not already installed):

• On Debian/Ubuntu:
  bash sudo apt install ncdu
• On Red Hat/CentOS:
  bash sudo yum install ncdu

1. Run ncdu:

   admin@atbytes:~$ ncdu /path/to/directory

• Navigate through directories using arrow keys.
• Press q to quit.

Example:

Analyze disk usage in the /var directory:

admin@atbytes:~$ ncdu /var

Output (Interactive):

--- /var ---------------------------------------------------------
    500.0 MiB [##########] /lib
    100.0 MiB [##]        /cache
     20.0 MiB [ ]         /log
    620.0 MiB [##########]  total

• Explanation:
  • Use arrow keys to navigate.
  • Press Enter to drill down into directories.
  • Press q to quit.

6. Using baobab (Graphical Disk Usage Analyzer)

If you prefer a graphical interface, you can use baobab (Disk Usage Analyzer).

1. Install baobab:

• On Debian/Ubuntu:
  bash sudo apt install baobab
• On Red Hat/CentOS:
  bash sudo yum install baobab

1. Launch baobab:

   admin@atbytes:~$ baobab

Select a directory (e.g., /home) to analyze.

Output (Graphical):

• A pie chart or treemap showing disk usage for the selected directory.

7. Using inxi (System Information Tool)

inxi is a versatile tool that provides detailed system information, including disk usage.

1. Install inxi:

• On Debian/Ubuntu:
  bash sudo apt install inxi
• On Red Hat/CentOS:
  bash sudo yum install inxi

1. Run inxi to check disk space:

   admin@atbytes:~$ inxi -D

Example:

admin@atbytes:~$ inxi -D

Output:

Drives:    HDD Total Size: 150.0GB
           ID-1: /dev/sda size: 50.0GB
           ID-2: /dev/sdb size: 100.0GB
Partition: ID-1: / size: 40.0GB used: 20.0GB (50%) fs: ext4 dev: /dev/sda1
           ID-2: /home size: 10.0GB used: 5.0GB (50%) fs: ext4 dev: /dev/sda2
           ID-3: /mnt/data size: 100.0GB used: 60.0GB (60%) fs: ext4 dev: /dev/sdb1

• Explanation:
  • Total disk size: 150GB.
  • /dev/sda1 (40GB) is 50% used.
  • /dev/sdb1 (100GB) is 60% used.

8. Using stat (File System Statistics)

The stat command can display information about a specific file or filesystem.

admin@atbytes:~$ stat -f /path/to/directory

• -f: Displays filesystem information.
• Output includes:
• Total size.
• Free space.
• Used space.

Example:

Check filesystem information for /home:

admin@atbytes:~$ stat -f /home

Output:

  File: "/home"
    ID: 1234567890abcd Namelen: 255     Type: ext4
Block size: 4096       Fundamental block size: 4096
Blocks: Total: 2621440    Free: 1048576    Available: 1048576
Inodes: Total: 655360     Free: 524288

• Explanation:
  • Block size: 4096 bytes.
  • Total blocks: 2,621,440 (10.5GB).
  • Free blocks: 1,048,576 (4.2GB).

Summary

• Quick overview: Use df -h.
• Detailed directory usage: Use du -sh.
• Interactive analysis: Use ncdu.
• Graphical tool: Use baobab.

Choose the method that best suits your needs.