I have a Windows 10 tablet which has a small 64GB hard drive that is always running close to full. It used to be quite a time consuming exercise going through the file system trying to find out where I was using up all the space until I came across WizTree.
It a elegant piece of software that creates a visual treemap of the used hard disk space. It lets you see where the majority of the space is being taken up and can reveal some large cache files that may no longer be needed.

Since installing WizTree it’s become much quicker for me to find out which files are taking up valuable space. The treemap is also interactive so you can hover your mouse over a square and find out the exact location of the offending files.

Even on larger hard disks it doesn’t take long for the software to complete its analysis as the software reads the Master File Table of the NTFS file system where the file size is already stored.
It’s only because the hard drive on my tablet is so small that I started doing this but now that I’ve discovered WizTree I’ve started using it on my other computers where I’ve got much larger hard disks.
Happy hunting.