Why the system preferences show iCloud storage of 1.01 gb available out of 5 gb different from the About this Mac -> Storage Window? Please help. My MacBook pro's iCloud storage suddenly got huge. How to fix?

Hi macRacFur,

Thanks for posting in Apple Support Communities! The storage you see in 'About This Mac' is for your Mac's internal hard drive, and is different than iCloud storage. This is why those numbers are not matching up.

If you'd like to free up space in iCloud, we suggest following the guidance in the article Manage your iCloud storage. Since it looks like the most space is being taken up by iCloud Drive, you can delete any unwanted files or folders there using these steps from the above article:

1. "Open the Finder and go to the iCloud Drive folder.
2. Drag an item to the Trash, or move it to a different folder on your Mac.
3. Open Trash, then right-click the files that you want to delete.
4. Select Delete Immediately. Then click Delete to confirm. "

Deleting those files will increase your available iCloud storage. If you want to free up space on your internal hard drive, follow these steps: Free up storage space on your Mac.

Hope that helps!

See the articles Find and delete files on your Mac - Apple Support

Delete files and folders on Mac - Apple Support

Delete shared folders or files in iCloud Drive - Apple Support

Note : you have dragged and dropped folder and files inside it over the location > finder > Macintosh HD see the article Work with files and folders in iCloud Drive – Apple Support