Solved Windows 11 Defrag Program and Defraggler Showing Totally Different Amount of Disk Fragmentation?

both programs don't look at the same files.
for example, Defraggler can be set to ignore the recycle bin, hibernation and paging files, and make sure you untick the option to include volume shadowing (VSS).
whereas the inbuilt defrag app has no controllable settings at all, so who knows what it includes/excludes.

I moved away from DF years ago, when I went to SSD's, I simply set Windows to TRIM it once a month.

HDD's should be defragged, in my humble opinion, only once or twice a year!

when I did use DF on HDD's, I used to go to the File List tab, analyse the drive, then click on the Fragments column header to sort descending, select the largest 50 or 100 or what have you and defrag that bunch.
then repeat the exercise the for Size column.

that way, you are getting rid of the worst offenders, both in number of fragments, and sheer space used.
in other words, the best outcome for the least work.

I haven't defragged my HDD in over five years, it's purely a dumping repository of stuff I don't want on my SSD, things like: Desktop, Downloads, Documents, Pictures etc - stuff I don't care if it takes 500ms to access 10 fragments on the HDD instead of 40ms to address the cells on the SSD.

in Defraggler, it allows you to move big files like that to the end of the drive.
I used to do that to my large, static files, to get them out of the way.

@Brandon Byrnes - any news?

no worries.