Operators

PowerShell provides a rich set of operators for comparison, arithmetic, logical operations, string manipulation, and more.

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Arithmetic Operators

Operator	Description	Example	Result
+	Addition / string concatenation	5 + 3	8
-	Subtraction	10 - 4	6
*	Multiplication / string repetition	"ha" * 3	"hahaha"
/	Division	10 / 3	3.3333...
%	Modulo (remainder)	10 % 3	1
-band	Bitwise AND	0xFF -band 0x0F	15
-bor	Bitwise OR	0x01 -bor 0x02	3
-bxor	Bitwise XOR	0xFF -bxor 0x0F	240
-bnot	Bitwise NOT	-bnot 0	-1
-shl	Shift left	1 -shl 4	16
-shr	Shift right	16 -shr 2	4

Assignment shorthand

$x = 10
$x += 5     # $x = 15
$x -= 3     # $x = 12
$x *= 2     # $x = 24
$x /= 4     # $x = 6
$x %= 4     # $x = 2
$x++        # $x = 3
$x--        # $x = 2

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Comparison Operators

PowerShell comparison operators are case-insensitive by default. Prefix with c for case-sensitive or i for explicit case-insensitive.

Operator	Meaning	Example
-eq	Equal	"a" -eq "A" → $true
-ne	Not equal	1 -ne 2 → $true
-gt	Greater than	5 -gt 3 → $true
-lt	Less than	3 -lt 5 → $true
-ge	Greater or equal	5 -ge 5 → $true
-le	Less or equal	4 -le 5 → $true
-like	Wildcard match	"hello" -like "h*" → $true
-notlike	Wildcard not match	"hello" -notlike "z*" → $true
-match	Regex match	"abc123" -match "\d+" → $true
-notmatch	Regex not match	"abc" -notmatch "\d+" → $true
-contains	Collection contains	@(1,2,3) -contains 2 → $true
-notcontains	Collection not contains	@(1,2,3) -notcontains 5 → $true
-in	Value in collection	2 -in @(1,2,3) → $true
-notin	Value not in collection	5 -notin @(1,2,3) → $true
-is	Type check	42 -is [int] → $true
-isnot	Negative type check	"a" -isnot [int] → $true

Case-sensitive variants

"Hello" -ceq "hello"    # $false (case-sensitive equal)
"Hello" -ieq "hello"    # $true  (explicit case-insensitive)
"Hello" -clike "H*"     # $true
"hello" -clike "H*"     # $false
"ABC" -cmatch "[A-Z]+"  # $true

Array filtering with comparison operators

When the left side is an array, comparison operators return matching elements:

1,2,3,4,5 -gt 3        # → 4, 5
"cat","dog","cow" -like "c*"  # → "cat", "cow"
"apple","banana","cherry" -match "^[ab]"  # → "apple", "banana"

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Logical Operators

Operator	Description	Example
-and	Both true	$a -and $b
-or	Either true	$a -or $b
-not / !	Negate	-not $a / !$a
-xor	Exactly one true	$a -xor $b

Short-circuit evaluation

-and stops at the first $false; -or stops at the first $true:

$file = ".\config.json"
if ((Test-Path $file) -and (Get-Content $file -Raw | ConvertFrom-Json)) {
    "Valid config found"
}

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String Operators

Operator	Description	Example
+	Concatenate	"Hello" + " World"
*	Repeat	"ab" * 3 → "ababab"
-f	Format	"Hello, {0}!" -f "Alice"
-replace	Regex replace	"hello" -replace "l","r" → "herro"
-split	Split by regex	"a,b,c" -split "," → @("a","b","c")
-join	Join array	@("a","b","c") -join "," → "a,b,c"

# -f format operator
"Today is {0:yyyy-MM-dd}" -f (Get-Date)
"{0,-15} {1,10:N2}" -f "Total", 1234.5

# -replace with regex groups
"John Smith" -replace "(\w+) (\w+)", '$2, $1'  # "Smith, John"

# -split with limit
"a:b:c:d" -split ":", 2   # @("a", "b:c:d")

# -join
("a","b","c") -join " | "  # "a | b | c"

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Redirection Operators

Operator	Meaning
>	Redirect stdout to file (overwrite)
>>	Redirect stdout to file (append)
2>	Redirect errors to file
2>>	Append errors to file
2>&1	Redirect errors to stdout
*>	Redirect all streams to file
*>>	Append all streams to file
3>	Redirect warning stream
4>	Redirect verbose stream
5>	Redirect debug stream
6>	Redirect info stream

Get-Process > .\procs.txt           # overwrite
Get-Process >> .\procs.txt          # append
Get-ChildItem C:\ 2> .\errors.txt   # capture errors
Get-ChildItem C:\ 2>&1 | Out-File .\all.txt  # combine streams

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Range Operator ..

1..10        # array: 1 through 10
10..1        # array: 10 down to 1
'a'..'z'     # array: 'a' through 'z' (returns char in PS 7.4+, int in earlier versions)
foreach ($i in 1..5) { $i }

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Null-Coalescing and Null-Conditional Operators (PS 7+)

# ?? null-coalescing
$value = $null
$value ?? "default"      # "default"
$value ??= "default"     # assign "default" to $value if null

# ?. null-conditional member access
$obj = $null
$obj?.Name               # $null (no exception)
$obj?.Method()           # $null (no exception)

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Ternary Operator (PS 7+)

$age = 20
$status = $age -ge 18 ? "adult" : "minor"

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Pipeline Chain Operators (PS 7+)

# && runs second command only if first succeeds
git pull && git push

# || runs second command only if first fails
Test-Path .\config.json || Write-Error "Config missing"