How to use Robocopy multithreaded option to speed up file copy on Windows 11

File Explorer copies files sequentially, which slows down large transfers on Windows 11.
Robocopy is a built-in tool designed for high-performance and reliable file transfers.
The /MT switch enables multithreaded copying, allowing multiple files to transfer at once.

On Windows 11, copying files to another drive usually means relying on the familiar select, copy, and paste workflow in File Explorer. If you’re transferring a small set of files, this approach works well enough. However, when you are dealing with large folders, thousands of files, or high-capacity drives, transfer speed quickly becomes a bottleneck, turning a simple task into a long wait.

A more efficient alternative is Robocopy (Robust File Copy), a built-in command-line tool on Windows 11. It’s been designed for reliability and performance. Robocopy offers advanced features that go far beyond what File Explorer can do, including resume support, detailed logging, and fine-grained control over how files are copied locally or over the network.

One of Robocopy’s most valuable and often overlooked capabilities is multithreaded file copying. Instead of transferring files one at a time, Robocopy can copy multiple files simultaneously, significantly reducing transfer times, especially on fast SSDs, NVMe drives, and high-bandwidth network connections.

In this guide, I’ll explain how to use Robocopy’s multithreaded copy feature to speed up transferring files and folders to another drive on Windows 11.

Using Robocopy’s multithreaded feature on Windows 11

To copy files and folders to another drive on Windows 11 using the Robocopy multithreaded feature, follow these steps:

Open Start on Windows 11.
Search for Command Prompt (or Terminal), right-click the result, and select the Run as administrator option.
Type the following command to copy the files and folders to another drive and press Enter:
```
robocopy C:\source\folder\path\ D:\destination\folder\path\ /S /E /Z /ZB /R:5 /W:5 /TBD /NP /V /MT:32
```
In the command, change the source and destination paths and the options. For example, this command copies data from the drive “C” to “D” and uses the “32” threads for copying:
```
robocopy C:\Users\admin\Documents D:\Users\admin\Documents /S /E /Z /ZB /R:5 /W:5 /TBD /NP /V /MT:32
```

Robocopy switches breakdown

Robocopy includes a wide range of switches that control how files are copied, verified, and retried. In the command used in this guide, the following switches are applied to improve reliability and maximize transfer performance, ensuring large file operations complete faster and with fewer errors.

/S — Copy subdirectories but skip empty ones.
/E — Copy subdirectories, including empty ones.
/Z — Copy files in restartable mode.
/ZB — Switch to backup mode if access is denied.
/R:5 — Retry 5 times before failing.
/W:5 — Wait 5 seconds before retrying.
/TBD — Wait if a share name is not yet available.
/NP — Suppress progress percentage.
/V — Show skipped files in verbose mode.
/MT:32 — Enable multithreaded copy with 32 threads (default is 8, max is 128).

The most important switch to focus on in the above command is /MT, which is the switch that enables Robocopy to copy files in multithreaded mode. If you do not set a number next to the /MT switch, the default number will be 8, which means that the tool will try to copy eight files simultaneously. However, Robocopy supports 1 to 128 threads.

In this command, I’m using 32, but you can set it to a higher number. The only caveat is that a higher number will result in higher resource usage and bandwidth consumption. Using a high value will degrade performance on older processors. As a result, test before executing the command with more threads.

Once you complete these steps, file transfers should be noticeably faster than using File Explorer, whether you are copying data to another drive or moving large volumes of files across the network.