Did a clean install of Windows, shows only 400GB free of 1TB(Capacity).Any ideas?

[Souvik Chatterjee]

Specs: i5-8250U
8GB RAM
1TB hdd
win 10
2GB 940MX
I just reset my pc, and was astonished to see that the hard drive was being invariably despite of no apps being installed. 404 GB free of 930 GB. I am absolutely clueless as to what is causing this. And to add to this, I have individually checked the sizes of the folders in OS(C) And was shocked to see that the sizes sum up to hardly 100 GB. Hidden folders? No idea
Any leads/ hints would be appreciated.
Thanks in advance
Regards

 

[rgd1101]

use windirstat https://windirstat.net/ to see what taking up space

 

[Souvik Chatterjee]

Thanks a ton! You're my Hero!
857GB free of 930 Gb!!
Yay