Funnel search
It groups by size — files of unique size are not even opened — then compares the hash of the first and last 64 KiB, and only on what remains computes the full SHA-256. That is what makes it usable on a whole disk.
The Deduplication module finds files with the same content in one or more folders and lets you remove the extra copies. It is the only Probatio feature that removes the user's files, and it is written accordingly: hash re-checked before every removal, no group ever left without a copy, a reversible action by default and a report of what was removed.
It groups by size — files of unique size are not even opened — then compares the hash of the first and last 64 KiB, and only on what remains computes the full SHA-256. That is what makes it usable on a whole disk.
Minutes can pass between the analysis and the action, and a file can change: before touching it Probatio recomputes its hash, and if it no longer matches it leaves the file where it is and says so.
The last copy of a group cannot be selected, and the engine rejects outright a group that would be left empty.
The default action moves, it doesn't delete: to the system trash or to a quarantine folder that keeps the path structure, so two same-named files from different folders don't overwrite each other. Permanent deletion must be chosen and confirmed separately.
Two paths pointing to the same content on disk are not two copies: deleting one frees nothing. Probatio recognises them and leaves them out of the recoverable space.
Keep the oldest copy, the newest or the one with the shortest path, or choose by hand group by group.
The groups found with their hashes and, if you acted, which files were removed and where they went. Worth generating before and after the action: the first one records every file's hash.