PowerShell cheat sheet

A single page to keep open while you work. Everything below runs in PowerShell 7 (pwsh) and, unless marked, in Windows PowerShell 5.1 as well. Lines starting with # are comments.

Help and discovery

Get-Command *network*                 # find cmdlets by name
Get-Command -Module Microsoft.PowerShell.Management
Get-Help Copy-Item -Examples          # examples for a cmdlet
Get-Help about_Operators              # conceptual help topics
Get-Alias                             # all aliases
Get-Alias -Definition Get-ChildItem   # aliases for one cmdlet
$PSVersionTable                       # which PowerShell is this?

Files and folders

Get-Location                                  # pwd
Set-Location C:\Projects                      # cd
Get-ChildItem                                 # ls
Get-ChildItem -Recurse -Filter *.log          # find by name
Get-ChildItem -Force                          # include hidden files
New-Item -ItemType Directory -Path .\build    # mkdir
New-Item -ItemType File -Path .\notes.txt     # touch
Copy-Item .\a.txt .\b.txt
Copy-Item .\src -Destination .\backup -Recurse
Move-Item .\old.txt .\new.txt                 # move or rename
Rename-Item .\report.txt report-final.txt
Remove-Item .\build -Recurse                  # rm -r
Test-Path .\config.json                       # does it exist? True/False
Get-Item .\a.txt | Select-Object Length, LastWriteTime
Resolve-Path .\..\other                        # absolute path

Reading and writing text

Get-Content .\app.log                         # cat
Get-Content .\app.log -Tail 20                # last 20 lines
Get-Content .\app.log -Wait                   # tail -f
Get-Content .\app.log | Select-String error   # grep (case-insensitive by default)
Select-String -Path *.log -Pattern 'timeout' -CaseSensitive
'hello' | Out-File .\out.txt                  # write (overwrite)
'more'  | Add-Content .\out.txt               # append
Set-Content .\out.txt -Value 'replace all'
(Get-Content .\a.txt) -replace 'foo', 'bar' | Set-Content .\a.txt

Filtering, sorting, shaping

Get-Process | Where-Object { $_.WorkingSet64 -gt 500MB }
Get-Process | Where-Object Name -like 'chrome*'       # simplified syntax
Get-Service | Sort-Object Status, Name
Get-ChildItem | Sort-Object Length -Descending | Select-Object -First 10 Name, Length
Get-Process | Select-Object Name, @{Name='MB'; Expression={ [math]::Round($_.WorkingSet64 / 1MB) }}
Get-ChildItem | Measure-Object -Property Length -Sum
Get-Service | Group-Object Status
Get-ChildItem | ForEach-Object { $_.Name.ToUpper() }

Processes, services, system

Get-Process
Get-Process -Name notepad
Stop-Process -Name notepad                # careful: ends the program
Start-Process notepad.exe
Start-Process pwsh -Verb RunAs            # new elevated window (Windows)
Get-Service -Name Spooler
Restart-Service -Name Spooler             # Windows, administrator
Get-ComputerInfo | Select-Object OsName, OsVersion, CsName     # Windows
Get-NetIPAddress -AddressFamily IPv4      # Windows
Test-NetConnection example.com -Port 443  # Windows
Get-Uptime                                # PowerShell 6+

Export and import data

Get-Service | Export-Csv services.csv -NoTypeInformation
Import-Csv services.csv | Where-Object Status -eq 'Running'
Get-Process | Select-Object Name, Id | ConvertTo-Json | Set-Content procs.json
Get-Content procs.json | ConvertFrom-Json
Invoke-RestMethod https://api.github.com/repos/PowerShell/PowerShell | Select-Object stargazers_count
Invoke-WebRequest https://example.com -OutFile page.html

Variables, arrays, hashtables

$x = 5
$list = @('a', 'b', 'c');  $list[0];  $list.Count
$list += 'd'
$map = @{ Name = 'Ana'; Role = 'admin' };  $map.Name;  $map['Role']
$map.Keys
$obj = [pscustomobject]@{ Host = 'web1'; Up = $true }
$env:PATH                               # environment variables live in $env:
$env:MY_SETTING = 'value'               # for this session only
$HOME; $PSScriptRoot; $PWD; $?; $LASTEXITCODE

Operators that differ from bash

• Comparison: -eq -ne -gt -ge -lt -le. Add c for case sensitive (-ceq).
• Strings: -like 'a*' (wildcards), -match '^a.*' (regex, sets $Matches), -replace, -split, -join.
• Collections: -contains, -in, -notcontains.
• Logic: -and -or -not (or !).
• && and || exist only in PowerShell 7. In 5.1 use ; and check $?.
• Call a program whose path is in a string or has spaces with &: & 'C:\Program Files\App\app.exe' --flag.
• Backtick ` is the escape and line-continuation character, not backslash.

Control flow

if ($x -gt 3) { 'big' } elseif ($x -eq 3) { 'three' } else { 'small' }
foreach ($f in Get-ChildItem *.txt) { $f.Name }
for ($i = 0; $i -lt 3; $i++) { $i }
while ($true) { break }
switch ($x) { 1 { 'one' } 5 { 'five' } default { 'other' } }
try { Get-Item missing.txt -ErrorAction Stop } catch { "Failed: $($_.Exception.Message)" } finally { 'done' }
function Get-Greeting { param([string]$Name = 'world') "Hello, $Name" }
Get-Greeting -Name Ana

Scripts

.\script.ps1                                  # run a script in the current folder
pwsh -NoProfile -File .\script.ps1 -Verbose    # run from cmd or a scheduler
Get-ExecutionPolicy -List                      # why won't scripts run?
$PROFILE                                       # path of your startup script
notepad $PROFILE                               # edit it (created if missing)

Remote machines (Windows)

Enter-PSSession -ComputerName server01               # interactive session
Invoke-Command -ComputerName server01, server02 -ScriptBlock { Get-Service W32Time }
Invoke-Command -ComputerName server01 -FilePath .\audit.ps1
ssh user@linuxhost                                   # OpenSSH client is built in

Remoting over WinRM has to be enabled on the target first (Enable-PSRemoting, run as administrator). Careful: that opens a listener and firewall rule; Disable-PSRemoting reverses it, and the documentation lists the extra cleanup steps.

Official documentation

• PowerShell module and cmdlet reference
• Operators in the language specification
• Running remote commands