How to Get Free Disk Space using PowerShell

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In today’s technology-driven world, managing disk space efficiently is crucial to ensuring the smooth functioning of your computer systems or servers. As files and applications continue to accumulate, it’s essential to monitor and analyze disk space regularly.

Thankfully, PowerShell, a powerful scripting language and automation framework from Microsoft, provides several convenient methods to check disk space effortlessly.

In this blog post, we will explore different PowerShell commands and scripts to get free disk space on your Windows machines.

PowerShell Check Disk Space: Get-Volume

The Get-Volume cmdlet in PowerShell lets you retrieve information about your computer’s volumes (logical drives).

Check Free Disk Space on All Volumes

To check the free disk space of all available volumes, open a PowerShell window and execute the following command:

Get-Volume

This command will display a detailed list of all volumes, their capacity, free space, and other essential information. The output will help you identify which volumes run low on disk space.

Check Free Disk Space on a Specific Drive Letter

By specifying the drive letter, you can limit the result to a specific volume. For example, the below command returns the free disk space information on drive D.

Get-Volume -DriveLetter D

Check Free Disk Space Based on Drive Type

In most cases, monitoring the disk space only applies to fixed disks. Using the Where-Object cmdlet, you can filter the output to show only the fixed disks.

This command gets all volumes information and filters the DriveType parameter matching the word ‘Fixed’.

Get-Volume | Where-Object {$_.DriveType -eq 'Fixed'}

Check Free Disk Space on Volumes with Assigned Drive Letters

Another way to filter results is to show only fixed drives with assigned drive letters. Take the sample command in the previous example. But this time, add another condition to show only volumes with non-empty drive letters.

Get-Volume | Where-Object {$_.DriveType -eq 'Fixed' -and $_.DriveLetter}

PowerShell Storage Module: Get-Disk, Get-Partition, and Get-PhysicalDisk

Modern Windows versions include the Storage PowerShell module, which provides detailed info about physical disks, partitions, and storage devices. While Get-Volume is useful for checking free space, storage cmdlets help you to troubleshoot capacity, partition layout, and hardware-related storage issues.

Here are some examples of usage. The following command displays physical disk info including disk number, size, partition style, and operational status:

Get-Disk |
Select-Object Number,FriendlyName,Size,PartitionStyle,OperationalStatus

The following command displays partition info, including drive letters and partition sizes:

Get-Partition |
Select-Object DiskNumber,PartitionNumber,DriveLetter,Size

View Physical Storage Devices

The Get-PhysicalDisk cmdlet provides hardware-level storage information such as health status, media type, and operational state. This command is especially useful in Storage Spaces and modern storage environments:

Get-PhysicalDisk |
Select-Object FriendlyName,MediaType,HealthStatus,OperationalStatus,Size

Note. Get-Disk, Get-Partition, and Get-PhysicalDisk focus on storage infrastructure rather than available free space. To check free capacity on volumes, you should use Get-Volume or Win32_LogicalDisk.

PowerShell Check Disk Space: Get-PSDrive

Another useful cmdlet for checking disk space is Get-PSDrive. While Get-Volume is specific to volumes, Get-PSDrive provides information about all the available drives, including file system drives and registry drives.

Check Free Disk Space on All Drives

Running this command will give you a list of drives and their properties, including available free space.

Get-PSDrive

Check Free Disk Space on FileSystem Drives Only

But as you can see, the command returned all PowerShell drives. But we’re only interested in the FileSystem provider. To get only the FileSystem drives, let’s use the -PSProvider parameter.

Get-PSDrive -PSProvider FileSystem

Check Free Disk Space on Specific Drives

You can also get free disk space for specific drives only by specifying the drive letter using the -Name parameter.

Get-PSDrive -Name C

PowerShell Check Disk Space: Win32_LogicalDisk Class

WMI (Windows Management Instrumentation) is a powerful feature in Windows that allows you to access system information, local or remote. In it, there are classes that expose this system information that you can query.

One such class is the Win32_LogicalDisk class, which includes the disk name, size, and free space. You can query this class using either Get-WmiObject or Get-CimInstance.

Both cmdlets can retrieve similar info from the Win32_LogicalDisk class. However, Get-WmiObject is only available in Windows PowerShell 5.1 and earlier. It is not available in PowerShell 7+ because PowerShell Core does not support the legacy WMI cmdlets. For modern scripts, automation, and cross-platform compatibility, you should use Get-CimInstance instead. You should use Get-WmiObject only when maintaining older Windows PowerShell scripts.

Check Free Disk Space on a Local or Remote Computer

For example, the following PowerShell check disk space commands query the disk information from the remote computer called DC1.

Get-CimInstance -Class Win32_LogicalDisk -ComputerName DC1 | ` 
Format-Table SystemName, DeviceID, DriveType, VolumeName, Size, FreeSpace -AutoSize

Note. If querying the local computer, remove the -ComputerName parameter entirely or replace the computer name with a dot (i.e., -ComputerName .)

Keep in mind that the FreeSpace and Size values are shown in bytes.

Check Free Disk Space on Multiple Computers

You can also query multiple machines at once by specifying their hostnames in the -ComputerName parameter. For example, to query DC1 and DC2, the command is:

Get-CimInstance -Class Win32_LogicalDisk -ComputerName DC1, DC2 | ` 
Format-Table SystemName, DeviceID, DriveType, VolumeName, Size, FreeSpace -AutoSize

Note. The Win32_LogicalDisk class does not return network-mapped drives on remote computers. To get mapped drives on remote machines, use the Win32_MappedLogicalDisk class instead.

Query Remote Computers with CIM Sessions

We recommend CIM sessions when you need to repeatedly query remote machines because they reuse the same management connection and reduce overhead:

$cim = New-CimSession -ComputerName DC1

Get-CimInstance `
-Class Win32_LogicalDisk `
-CimSession $cim

When finished, close the CIM session:

Remove-CimSession $cim

Check Free Disk Space with WMI Filter

While a machine can have different drive types, monitoring mostly makes sense only on local disks. When running the PowerShell check disk space query with Get-WMIObject or Get-CIMInstance, you can filter the drive type to return.

Below is the list of available drive types:

• 0 = Unknown
• 1 = No Root Directory
• 2 = Removable Disk
• 3 = Local Disk
• 4 = Network Drive
• 5 = Compact Disc
• 6 = RAM Disk

We know that the fixed or local drive type number is 3. So we can add the -Filter “DriveType = 3” filter.

Get-CimInstance -Class Win32_LogicalDisk -ComputerName DC2 -Filter "DriveType = 3" |
Format-Table SystemName, DeviceID, DriveType, VolumeName, Size, FreeSpace -AutoSize

In case you maintain legacy Windows PowerShell 5.1 scripts, you may encounter Get-WmiObject examples. However, PowerShell 7+ does not include the Get-WmiObject cmdlet, so you should use Get-CimInstance for all modern scripts and automation cases.

Find Volumes Running Low on Free Space

In real-world environments, you may be interested in identifying disks that are running low on free space rather than simply displaying all volumes. PowerShell makes it easy to filter volumes based on available capacity thresholds.

Example 1: Find Volumes with Less Than 10% Free Space

The following command displays volumes that have less than 10 percent of their total capacity remaining:

Get-Volume |
Where-Object {
$_.SizeRemaining / $_.Size -lt 0.1
} |
Sort-Object SizeRemaining

Example 2: Display Free Space Percentage

The following example calculates and displays the percentage of free space available on each volume:

Get-Volume |
Select-Object DriveLetter,
@{
Name='FreeSpacePercent'
Expression={
[math]::Round(
($_.SizeRemaining / $_.Size) * 100,
2
)
}
}

Example 3: Filter Local Disks Using CIM

The following method works on local/remote machines and returns only fixed disks with less than 10 percent free space remaining:

Get-CimInstance Win32_LogicalDisk -Filter "DriveType=3" |
Where-Object {
($_.FreeSpace / $_.Size) -lt 0.1
}

In order to display disk space in GB, run the following command:

Get-CimInstance Win32_LogicalDisk -Filter "DriveType=3" |
Select-Object DeviceID,
@{
Name='SizeGB'
Expression={[math]::Round($_.Size/1GB,2)}
},
@{
Name='FreeGB'
Expression={[math]::Round($_.FreeSpace/1GB,2)}
}

Example 4: Show Volumes with Less Than 20 GB Free

The following command returns all volumes with less than 20 GB of free space:

Get-Volume |
Where-Object {
$_.SizeRemaining -lt 20GB
}

Tip. Monitoring solutions typically use threshold-based checks (for example, less than 10% free space or less than 20 GB remaining) rather than displaying raw disk statistics. Note that these thresholds can be integrated into scheduled PowerShell scripts, monitoring platforms, or alerting systems.

Up to this point, the examples focused on one-time disk space checks using built-in PowerShell commands. In many environments, these commands are sufficient for daily administration.

If you need to collect disk space info from multiple machines, generate reports, or integrate the results into monitoring workflows, you can wrap the logic into a reusable PowerShell function.

Most Common Disk Space Commands

For quick administrative tasks, the following commands are usually sufficient:

You can check all volumes with the command:

Get-Volume

In order to check local disks only, use the following command:

Get-CimInstance Win32_LogicalDisk -Filter "DriveType=3"

You can find volumes with less than 10% free space using the command:

Get-Volume |
Where-Object {
$_.SizeRemaining / $_.Size -lt 0.1
}

To query a remote server, use the following command:

Get-CimInstance Win32_LogicalDisk `
-ComputerName SRV01 `
-Filter "DriveType=3"

If these commands meet your requirements, there is no need to use a custom function. The script below is intended for larger environments where the same check must be performed repeatedly across multiple servers.

Advanced: Create a Reusable Disk Space Reporting Function

Running the PowerShell check disk space commands manually is suitable for ad-hoc work. But it would be best to convert the commands into a reusable script or function that anyone can use without modifying the code.

Here’s a PowerShell script called Get-DiskSpace. You can also download this script from this Gist. This function can retrieve the disk space information on local and remote computers and display them in an easy-to-understand result.

Function Get-DiskSpace { 
[CmdletBinding()] 
param ( 
[Parameter()] 
[String[]] 
$ComputerName = $env:COMPUTERNAME 
) 

# Drive type lookup table 
$driveType = @{ 
0 = 'Unknown' 
1 = 'No Root Directory' 
2 = 'Removable Disk' 
3 = 'Local Disk' 
4 = 'Network Drive' 
5 = 'Compact Disc' 
6 = 'RAM Disk' 
} 

$result = [System.Collections.ArrayList]@() 
foreach ($computer in $ComputerName) { 
try { 
if ($localLogicalDisks = Get-CimInstance -Class Win32_LogicalDisk -ComputerName $computer -Property * -ErrorAction Stop) { 
$result.AddRange($localLogicalDisks) 
if (($localLogicalDisks.DriveType) -notcontains 4) { 
if ($mappedLogicalDisks = Get-CimInstance -Class Win32_MappedLogicalDisk -ComputerName $computer -Property * -ErrorAction Stop) { 
$result.AddRange($mappedLogicalDisks) 
} 
} 
} 
} 
catch { 
"[ERROR][$computer] : $($_.exception.message)" | Out-Default 
} 
} 
if ($result) { 
$result | ForEach-Object { 
[PSCustomObject]@{ 
ComputerName = $_.SystemName 
DeviceID = $_.DeviceID 
VolumeName = $_.VolumeName 
DriveType = $( 
if ($_.DriveType) { 
$driveType[$([int]$_.DriveType)] 
} 
else { 
$driveType[4] 
} 
) 
SizeGB = $(
if ($null -ne $_.Size) {
[System.Math]::Round(($_.Size / 1GB), 2)
}
else {
$null
}
) 
UsedSpaceGB = $(
if ($null -ne $_.Size -and $null -ne $_.FreeSpace) {
[System.Math]::Round(
(($_.Size - $_.FreeSpace) / 1GB),
2
)
}
else {
$null
}
)
FreeSpaceGB = $(
if ($null -ne $_.FreeSpace) {
[System.Math]::Round(($_.FreeSpace / 1GB), 2)
}
else {
$null
}
) 
FreeSpacePercent = $(
if ($_.Size -gt 0) {
[System.Math]::Round(
(($_.FreeSpace / $_.Size) * 100),
2
)
}
else {
$null
}
) 
} 
} 
} 
}

Note. The function performs an additional query against the Win32_MappedLogicalDisk class only when no network drives (DriveType = 4) are returned by Win32_LogicalDisk. This helps you to capture mapped network drives that are often missing from remote CIM/WMI queries while avoiding duplicate entries when network drives are already present in the results.

How to Use this PowerShell Check Disk Space Function?

Save the script on your computer and name it Get-DiskSpace.ps1. Open PowerShell and change the working directory to where you saved the script.

When you run the script without the -ComputerName parameter, only the local computer will be queried by default.

.\Get-DiskSpace.ps1 | Format-Table

To query one or more computers, specify the computer names in the -ComputerName parameter.

.\Get-DiskSpace.ps1 -ComputerName DC1,DC2 | Format-Table

What happens if you specify a wrong or non-existing computer name? The script will display an error and skip that computer. For example, I included a DC3 in the query, but it does not exist.

You can also output the result to a CSV, JSON, Text, and other file formats by piping to the corresponding conversion cmdlets, like, Export-Csv, ConvertTo-JSON, Out-File, etc. Take it further by exporting and formatting the report in beautiful HTML files.

Practical Reporting and Automation Examples

In production environments, disk space info is often exported, scheduled, or integrated into monitoring workflows. The following examples demonstrate common admin tasks.

Example 1: Export Disk Space Report to CSV

The following command exports volume info to a CSV file that can be opened in Microsoft Excel/imported into reporting systems:

Get-Volume |
Select-Object DriveLetter,
@{
Name='FreeSpaceGB'
Expression={
[math]::Round(
$_.SizeRemaining / 1GB,
2
)
}
} |
Export-Csv C:\Reports\DiskSpace.csv -NoTypeInformation

Example 2: Generate an HTML Report

You can use HTML reports because they are useful for dashboards, documentation, or email distribution:

Get-Volume |
Select-Object DriveLetter,
FileSystemLabel,
Size,
SizeRemaining |
ConvertTo-Html |
Out-File C:\Reports\DiskSpaceReport.html

Example 3: Find Critical Volumes

The following example identifies volumes with less than 10 percent free space remaining:

Get-Volume |
Where-Object {
$_.SizeRemaining / $_.Size -lt 0.1
}

In rare cases, some devices (such as empty optical drives) may report a volume size of 0. When using percentage-based calculations in production scripts, you should consider adding a check to avoid division-by-zero errors.

Example 4: Generate Alert-Friendly Output

The output can be consumed by monitoring systems/scheduled scripts:

Get-Volume |
Where-Object {
$_.SizeRemaining / $_.Size -lt 0.1
} |
Select-Object DriveLetter,
@{
Name='FreePercent'
Expression={
[math]::Round(
($_.SizeRemaining / $_.Size) * 100,
2
)
}
}

Example 5: Schedule a Daily Disk Space Check

To automate disk space monitoring, you need to save the script as a .ps1 file and execute it through Windows Task Scheduler on a daily/hourly basis. This method is commonly used to generate reports and identify low disk space conditions before they impact services.

Common Disk Space Commands

Task	Recommended Command
Check all volumes	Get-Volume
Check physical disks	Get-Disk
Check partitions	Get-Partition
Check storage hardware	Get-PhysicalDisk
Check remote servers	Get-CimInstance
Find low disk space volumes	Get-Volume + Where-Object
Generate reports	Export-Csv / ConvertTo-Html

Conclusion

Using the above PowerShell commands and script, you can effortlessly keep track of disk space on your Windows machines, ensuring that you never run out of space and maintain optimal system performance.

In conclusion, PowerShell is a versatile tool simplifying disk space monitoring and management. Whether you want to check individual volumes, all drives, or multiple servers, PowerShell provides various methods to make the process efficient and effective.

Keeping an eye on disk space is an essential part of system maintenance, and with PowerShell, it becomes a breeze. You can also export PowerShell output to CSV, HTML, JSON, or monitoring platforms, making it suitable for enterprise reporting and automation cases. Happy scripting!