File decryption is almost always limited by the speed of the storage that files are decrypted from and to. A modern CPU can easily decrypt 10 GB of data per second, but most organizations will not have storage that is anywhere near that fast.
To decrypt files, our tools need to, approximately, read every file once and write it once.
Clients can benchmark their storage, get their read and write speeds, and then create an estimate specific for their setup using the formula: Amount of data encrypted / read speed + amount of data encrypted / write speed.
As a rough guideline, given commodity hardware, our tools will decrypt about 180 GB of data per hour on mechanical hard disks, about 1 TB per hour on SSDs, and about 3.5 TB per hour on NVMe drives.