Performance is the primary reason Microsoft has not included the functionality to display folder sizes in the Size column. For example, if you have a folder on the C drive, Windows would need to scan all the contents within the folder—including subfolders and both large and small files—to calculate its total size. This process requires significant resources, which would ultimately impact Windows’ performance.

The process becomes even more demanding when you open a drive with multiple folders, each containing additional subfolders. Calculating the total size of all those folders would put a heavy strain on Windows.

However, when you hover your mouse cursor over a folder, Windows displays its size after a small delay. This is possible because Windows only needs to calculate the size of that specific folder, not all the folders within the drive, making the process more feasible and efficient.

While Windows has yet to introduce the functionality to display folder size in the Size column, you can use a third-party application called Windhawk to achieve this feature. The application is safe to use, as verified by VirusTotal tests.

To get started, visit Windhawk’s official website, then download and install the application on your computer.

Once the installation is complete, open the application and click the “Browse for Mods” option.

In the search bar, type Better File Sizes in Explorer Details. Then, click the “Details” button under the relevant result.

Click the “Install” button.

After the mod is installed, switch to the “Settings” tab and select the “Enabled, Calculated Manually (Can Be Slow)” option from the Show Folder Sizes drop-down menu. Finally, click “Save Settings” to apply the changes.

Restart your computer, and you’ll see File Explorer displaying the size of all folders in the Size column.

When you no longer want to use the installed mod, open the application, click the “Home” tab, and disable the toggle for the mod you want to temporarily turn off under the Installed Mods section.

If you want to remove the mod entirely, click the “Remove” button and choose “Remove Mod” from the confirmation box that appears. Alternatively, you can uninstall the Windhawk application, which will automatically uninstalls the mod as well.

One important thing to keep in mind is that since Windhawk is a third-party application, any Windows update might break the folder size functionality. From my experience, Windhawk regularly releases updates for its mods, so whenever you get a Windows update, make sure to check for updates to the installed mod and download them to ensure it continues working as intended.

This is how I got Windows 11 to show folder sizes, and you can do it too. However, keep in mind that with the folder mod installed, you might notice that File Explorer takes a bit more time to display all the folders since it now has to show the folder sizes as well. If you’re okay with that slight delay, the Windhawk mod can be a great help.