How to Get the Length of a String in PowerShell

To get the length of a string in PowerShell, read its .Length property. It returns the number of characters, including spaces:

$city = 'San Francisco'
"'$city' has $($city.Length) characters"

Output:

'San Francisco' has 13 characters

That works for everyday text. Arrays, numbers, emoji and byte counts behave differently, and I cover each one below. I ran every example in PowerShell 7.6 and Windows PowerShell 5.1, with the same results.

Common .Length surprises

$names = 'Alice', 'Bob', 'Christopher'
$zip   = 78701

"Array .Length:        $($names.Length) (the number of items)"
"Longest name:         $(($names | Measure-Object -Property Length -Maximum).Maximum)"
"Number .Length:       $($zip.Length)"
"As text:              $($zip.ToString().Length)"
"Padded ' Austin '.Length: $(' Austin '.Length), trimmed: $(' Austin '.Trim().Length)"

Output:

Array .Length:        3 (the number of items)
Longest name:         11
Number .Length:       1
As text:              5
Padded ' Austin '.Length: 8, trimmed: 6

On an array, .Length is the number of items, not the length of each string. A number isn’t text, so .Length returns 1. Convert it with .ToString() first.

Spaces count too, so trim input before you measure it.

Emoji and accented letters

.Length counts UTF-16 code units, not the characters you see. Most letters are one unit, but an emoji can be two:

$thumb = [char]::ConvertFromUtf32(0x1F44D)    # the thumbs-up emoji
$cafe  = "Caf$([char]0xE9)"                    # Cafe with an accented e

"Emoji .Length:           $($thumb.Length)"
"Emoji characters you see: $([System.Globalization.StringInfo]::new($thumb).LengthInTextElements)"
"'$cafe' .Length:          $($cafe.Length)"

Output:

Emoji .Length:           2
Emoji characters you see: 1
'Café' .Length:          4

If you’re checking a limit that a person sees, like a display name, StringInfo.LengthInTextElements counts visible characters. Microsoft covers it in the StringInfo documentation.

Get the length of a string in bytes

The number of bytes depends on the encoding. Database columns, APIs and file formats often have byte limits, not character limits:

$cafe = "Caf$([char]0xE9)"

"UTF-8 bytes:  $([System.Text.Encoding]::UTF8.GetByteCount($cafe))"
"UTF-16 bytes: $([System.Text.Encoding]::Unicode.GetByteCount($cafe))"
"ASCII bytes:  $([System.Text.Encoding]::ASCII.GetByteCount('Austin'))"

Output:

UTF-8 bytes:  5
UTF-16 bytes: 8
ASCII bytes:  6

The accented é takes two bytes in UTF-8, so the four-letter word needs five bytes. In UTF-16, the encoding .NET uses in memory, every character here takes two.

Byte counts also matter for encodings like Base64, covered in converting a string to Base64.

Count specific characters, letters or digits

[regex]::Matches() counts anything you can describe with a pattern:

$text = 'Order 1042 ships to Austin on Monday'

"Letter a:  $(([regex]::Matches($text, 'a', 'IgnoreCase')).Count)"
"Letters:   $(([regex]::Matches($text, '[A-Za-z]')).Count)"
"Digits:    $(([regex]::Matches($text, '\d')).Count)"
"Spaces:    $(([regex]::Matches($text, ' ')).Count)"
"Words:     $(($text -split '\s+').Count)"

Output:

Letter a:  2
Letters:   26
Digits:    4
Spaces:    6
Words:     7

The 'IgnoreCase' option counts both a and A. For whole files instead of strings, see counting lines and words in a file.

Enforce a length on function parameters

Instead of checking the length inside a function, let PowerShell reject values that are too short or too long:

function Set-SiteCode {
    param(
        [ValidateLength(3, 8)]
        [string]$Code
    )
    "Site code set to $Code"
}

Set-SiteCode -Code 'ATX01'
try { Set-SiteCode -Code 'AUSTIN-DOWNTOWN' } catch { 'Rejected: the code must be 3 to 8 characters' }

Output:

Site code set to ATX01
Rejected: the code must be 3 to 8 characters

[ValidateLength(3, 8)] takes the minimum and maximum. about_Functions_Advanced_Parameters lists the other validation attributes.

Frequently Asked Questions

For more work with strings: