Disclosed herein are techniques for encrypting data stored on a solid-state drive (SSD) managed by a system (e.g., a computing device). Specifically, the system is configured to track block units of a larger size on the SSD so that a mapping table associated with the SSD can be kept small. After running SSD encryption using the large size block units, the entire SSD can be fully encrypted without requiring clear text to be written onto the SSD subsequent to SSD encryption being activated. Thereafter, the entire SSD can be defragmented to produce a single physical extent of encrypted data.