DiskGeek

DiskGeek scans any folder or drive and shows exactly where the disk space went.
A sortable list view is the fastest way to see what is biggest.

A squarified treemap makes the largest consumers obvious at a glance. Duplicate detection works byte for byte and, for images, by perceptual hash, so near-identical photographs are found as well as exact copies. Snapshots let two scans be compared over time.

Scanning runs on a background thread with a live file, folder and byte counter and a Cancel button, so the interface never locks up even on very large volumes.

No Pro tier, no ads and no bundled offers. Windows 10 1809 or later, 64-bit. Free to use, including at work.