How to split a file using built-in Windows functionalities

This post explains how to split a file using built-in Windows 11 functionalities.

You can always use 7-zip or a similar tool, but they’re not available on all systems.

Step-by-step instructions

1. Compress the file
2. Split the file
3. Merge the file

1. Compress the file

Compress the file from the GUI (right click > compress file).

Alternatively, you can do it using the Power Shell:

Compress-Archive -Path "C:\Path\To\Folder\*" -DestinationPath "C:\Output\myarchive.zip"

2. Split the file

Copy this code into a .ps1 file, or type this in a PowerShell terminal

$source = "C:\Output\myarchive.zip"
$destDir = "C:\Output"
$partSize = 20MB
$buffer = New-Object byte[] $partSize
$in = [System.IO.File]::OpenRead($source)
$index = 1

while ($bytesRead = $in.Read($buffer, 0, $buffer.Length)) {
    $partName = Join-Path $destDir ("myarchive.part{0:D3}.zip" -f $index)
    $out = [System.IO.File]::Create($partName)
    $out.Write($buffer, 0, $bytesRead)
    $out.Close()
    $index++
}
$in.Close()

If you created a .ps1 file, you can run it by right-clicking on it and selecting “Run”.

3. Merge the files

Type this in the Power Shell terminal:

Get-ChildItem "C:\Output\myarchive.part*.zip" | Sort-Object Name | Get-Content -Encoding Byte -ReadCount 0 | Set-Content -Encoding Byte "C:\Output\myarchive_joined.zip"