Defragger
github.com
What it is
Defragger is a graphical Linux tool for examining and defragmenting filesystems, with a map showing file, free-space, and metadata allocation. Its analysis identifies fragmentation and displays filesystem blocks in an adaptive map. The project supports online defragmentation of ext4 and offline defragmentation and compaction of FAT16 and FAT32. FAT12 and exFAT can be analyzed, but not modified. A command-line interface can list, analyze, defragment, and compact volumes. The interface and command-line program run without elevated privileges; operations that need them use a PolicyKit-authorized helper over D-Bus. The stated environment is Linux with Qt 6 and KDE Kirigami; privileged mode also requires systemd, PolicyKit, and an active graphical PolicyKit agent. For ext4, Defragger uses Linux filesystem ioctls directly rather than calling e4defrag or filefrag. The project labels the software alpha, recommends backing up important data, and says ext4 has received the most testing. FAT write support is newer, so it recommends beginning with disposable or fully backed-up volumes. The software is dual-licensed under MIT or Apache License 2.0.
Spec sheet
- Purpose
- Defragger is a graphical Linux filesystem defragmenter that visualizes file, free-space, and metadata allocation.Read 4 Oct 2026 · github.com
- Integrations
- For ext4 operations, Defragger uses Linux filesystem ioctls directly and says it does not shell out to e4defrag or filefrag.Read 4 Oct 2026 · github.com
- Support
- The repository exposes GitHub Issues, which showed zero open issues when viewed.Read 4 Oct 2026 · github.com
- License
- Defragger is dual-licensed under MIT or Apache License 2.0.Read 4 Oct 2026 · github.com
- Maker
- The README credits copyright 2026 to Guillaume Binet, and the maker's GitHub profile lists Austin, TX.Read 4 Oct 2026 · github.com
- Analysis
- It analyzes fragmentation and displays an adaptive filesystem block map.Read 4 Oct 2026 · github.com
- CLI
- The project includes a command-line interface for listing, analyzing, defragmenting, and compacting volumes.Read 4 Oct 2026 · github.com
- Data safety
- The README warns that the software is alpha, recommends backing up important data, and says ext4 has received the most testing.Read 4 Oct 2026 · github.com
- FAT caution
- FAT write support is newer and the README recommends first using it with disposable or fully backed-up volumes.Read 4 Oct 2026 · github.com
- Filesystem support
- It supports online ext4 defragmentation and offline FAT16/FAT32 defragmentation and compaction.Read 4 Oct 2026 · github.com
- Linux requirements
- The stated environment is Linux with Qt 6 and KDE Kirigami, while privileged mode requires systemd, PolicyKit, and an active graphical PolicyKit agent.Read 4 Oct 2026 · github.com
- Privilege handling
- The GUI and CLI run unprivileged, with elevated operations handled by a PolicyKit-authorized helper over D-Bus.Read 4 Oct 2026 · github.com
- Read-only formats
- FAT12 and exFAT support analysis only; neither is writable.Read 4 Oct 2026 · github.com
Plans and prices
Open-source Free Alpha software · Linux only · ext4 and offline FAT16/FAT32 write support Read 4 Oct 2026 · github.com
Strong points and limits
Strong points
- Adaptive map shows file and metadata allocation
- Supports online ext4 defragmentation
- FAT16 and FAT32 support offline compaction
- CLI can analyze and compact volumes
- Dual-licensed under MIT or Apache License 2.0
Limits
- The project describes the software as alpha
- FAT12 and exFAT are analysis-only
- FAT write support is newer
- Requires Linux, Qt 6, and KDE Kirigami
Who it suits
Defragger may suit Linux users who need to inspect filesystem allocation and work with supported ext4 or FAT volumes. Users considering FAT write operations should note the project’s recommendation to start with disposable or fully backed-up volumes.
Verdict
Defragger covers both graphical inspection and command-line volume operations, with different write support by filesystem. Its alpha status and backup guidance matter, especially for newer FAT write support.
Where Specifiction places it
- Disk Defragmentation Software#6 of 207.7
