How to Encode a File Contents into Base64 with Powershell

The aim of this page📝 is to explain how to handle file content in PowerShell based on the particular example of encoding a file’s content in Base64. This is to simulate "`base64"` command from bash with the bit of luxury that I want the encoded string directly copied to the clipboard as I'm setting that into Hashicorp Consul as a configuration value, in my particular case I've been working on setting TLS certificates there. For a comparison with Python, see https://medium.com/p/b5b5c3ff8b4/edit

2 min readOct 19, 2023

function b64 ($file_path) {
    $content = Get-Content -Path $file_path -Raw
    $byte_array = [System.Text.Encoding]::UTF8.GetBytes($content)
    $base64 = [System.Convert]::ToBase64String($byte_array)
    Write-Host "Original Content:" -foregroundcolor darkcyan
    Write-Host $content
    Write-Host "--------------------------------------------" -foregroundcolor darkcyan
    Write-Host "Base64 Encoded Content:" -foregroundcolor darkcyan
    Write-Host $base64
    Write-Host "--------------------------------------------" -foregroundcolor darkcyan
    Write-Host "+ Clipped" -foregroundcolor darkcyan
    Set-Clipboard -Value $base64
}

This script reads the content of a file as a single string, preserving newlines. It then converts this string to a byte array using UTF-8 encoding.
The byte array is then converted to a Base64 string. Both the original and encoded content are printed to the terminal.
Finally, the encoded content is copied to the clipboard.
In PowerShell, you can read the content of a file using the Get-Content cmdlet.
The Get-Content cmdlet reads the content line by line and returns an array of strings, each representing a line of content.
If you want to preserve the newlines in the content, you can use the -Raw parameter with Get-Content, which reads the content as a single string.
To convert a string to a byte array in PowerShell, you can use the GetBytes method of the System.Text.Encoding class.
The System.Text.Encoding class provides methods to convert strings to byte arrays and byte arrays to strings.
The UTF8 property of the System.Text.Encoding class gets an encoding for the UTF-8 format.
To convert a byte array to a Base64 string in PowerShell, you can use the ToBase64String method of the System.Convert class.
The System.Convert class provides methods to convert base data types to other base data types.
You can print content to the terminal in PowerShell using the Write-Host cmdlet.
The Write-Host cmdlet customizes output. You can specify colors for foreground and background, and also apply formatting.
To copy content to the clipboard in PowerShell, you can use the Set-Clipboard cmdlet.
The Set-Clipboard cmdlet sets the current clipboard entry. You can specify text or specify a file whose contents will be added to the clipboard.

How to Encode a File Contents into Base64 with Powershell

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Written by Pavol Kutaj