O&O Defrag

Last updated
O&O Defrag
Developers O&O Software
Stable release
30.5.1211 / December 12, 2025
Operating system Windows NT 4.0 to Windows 11
Type Defragmentation
License Shareware
Website oo-software.com

O&O Defrag is a Windows defragmentation utility sold by German software developer O&O Software. It has won several awards [1] by PC journals and magazines, and is certified by Microsoft [ citation needed ] for all its current NTFS-based operating systems, including NT 4.0, 2000, XP, Vista, 7, 8, 8.1, 10, 11, Server 2003, 2008, 2008 R2, 2012, 2012 R2, 2016, 2019, 2022 and 2025.

Contents

Features

There are five different defrag methods: Stealth, Space, Complete/Name, Complete/Modified, Complete/Access. "Stealth" is designed for use on PCs with large files and little free space, while the "Space" method is designed for heavily fragmented drives. The three "Complete" methods (Name, Modified and Access) sort the files on your drives alphabetically, according to date last changed, and according to date last accessed.

Simple defragmentation as on a hard drive is unnecessary and significantly wears the cells of a solid-state drive (SSD). O&O Defrag claims to defragment using the SSD TRIM command [2] :6 in a way that both increases access speed and reduces wear, extending the life of an SSD. [2] :7

Reviews

O&O Defrag was reviewed by CHIP magazine in 2025. [3]

See also

References

  1. "CHIP magazine tests 6 Defragmentation programs: O&O Defrag V8.6 is once again the Editors Choice!". O&O Software. March 2007. Archived from the original on July 21, 2011. Retrieved June 10, 2011.
  2. 1 2 "Defragmenting SSDs". O&O Defrag 30 (manual) (PDF). O&O. 8 January 2026.
  3. "O&O Defrag Professional 30.5". CHIP (in German). 4 November 2025.

Further reading