How long does it take to certify a disk

The certification process takes approximately one day per 2TB of capacity over Thunderbolt. There are no shortcuts, as the process involves writing to the entire drive and then reading the data back three times.

Since drives are typically sold with minimal or no testing, running a certification is the only way to identify potential defects in the drive or system upfront. A properly functioning set of drives should never fail certification.

The estimated time may vary depending on the drive’s location being tested, as inner tracks tend to be significantly slower.