GNU ddrescue

GNU ddrescue is a command-line recovery utility for copying data from failing files and block devices. It suits technically confident users who need automated, restartable rescue jobs across many kernel-supported devices. Its strongest case is controlled, incremental recovery; it is a poor fit if you want a graphical, file-oriented undelete workflow.

Overview

ddrescue copies readable data first when errors occur, then schedules bad or slow areas for later. That ordering limits needless drive movement and gets the most accessible data to safety early. The basic operation runs automatically through read errors, so you do not have to stop and restart manually at every failure.

A mapfile records progress. If a job is interrupted, you can resume it and reread only the blocks still needing attention rather than starting over. This makes long recoveries practical, especially with unstable disks or removable media.

Key features

• Broad source support: Recover from files, partitions, optical media and kernel-supported devices such as ATA, SATA, SCSI, floppy disks and SD cards. Memory-card recovery is explicitly supported.
• Direct access: Where the system permits it, direct disc access can bypass the kernel cache, giving operators another way to control reads during recovery.
• Operational modes: Fill mode selectively writes output areas, while generate mode creates an approximate mapfile from an input and partial copy. These are specialist tools for refining or continuing complex jobs.
• Mapfile utilities: The bundled ddrescuelog can manipulate and convert mapfiles, compare them and report rescue status. ddrescueview, ddrutility and Partclone are linked for related mapfile viewing and recovery workflows.
• Important constraints: A destination device or partition is overwritten, so choosing the target incorrectly can destroy data. ddrescue also cannot write a compressed image directly because recovery requires random access; create an uncompressed image first, then compress it.

Pricing

GNU ddrescue — free. It is free software under the GNU General Public License version 2 or any later version, with no paid plans stated and no free trial. That removes licensing cost for personal, repair-shop or institutional use, but does not provide a commercial support tier; bug reports and discussion go through the bug-ddrescue mailing list.

Platforms

GNU ddrescue targets Linux and other POSIX systems, and can be self-hosted. Windows users can use Cygwin, but the manual recommends a POSIX system and warns that Cygwin may produce misleading permission errors. That caveat makes native Linux or another POSIX environment the safer choice for important recoveries.

Who it's for

Choose ddrescue when you need sector-level imaging, resumable jobs and a process that keeps working through read errors. It is particularly suitable for administrators, data-recovery technicians and advanced users handling failing disks, optical media or flash cards. Look elsewhere if you need guided file selection, a visual interface or a recovery tool designed primarily for nontechnical Windows users.

Pros and cons

Pros

• Resumable mapfiles: Interrupted jobs continue without repeating completed reads.
• Automatic, prioritized recovery: Readable areas are captured first, while difficult regions wait, improving early yield and reducing unnecessary movement.
• Wide device coverage: Kernel-supported ATA, SATA, SCSI, floppy and flash media devices are in scope.
• Free and open source: GPL licensing removes purchase barriers and permits use without a paid plan.

Cons

• High-risk destination handling: Selecting a device or partition as the destination overwrites its existing data.
• Compression requires a second step: You must create an uncompressed image before compressing it.
• POSIX-first operation: Cygwin can produce misleading permission errors, making Windows recovery less dependable.
• Technical workflow: Mapfiles, direct access and specialist modes favor experienced operators over casual users.

Alternatives

For a broader directory of choices, see Data recovery software.

• EaseUS Data Recovery Wizard is the better pick for a freemium, multi-platform recovery app spanning Android, iOS, macOS and Windows, with a one-month plan at 69.95 USD.
• TestDisk is a free alternative for partition recovery, boot-sector repair and file undelete on Linux, macOS and Windows.
• Disk Drill suits macOS or Windows users who want a freemium desktop tool; its free Windows edition recovers up to 100 MB.
• PhotoRec is a free, open-source, multi-platform file-recovery option under GNU GPL v2 or later.
• MiniTool Power Data Recovery fits home users wanting a Windows or macOS freemium app with a 1 GB free recovery limit.
• AOMEI FastRecovery is a Windows freemium choice offering up to 500 MB free recovery and full-file previews.
• Ontrack EasyRecovery provides a freemium macOS/Windows workflow with a free tier capped at 1 GB and files under 25 MB, plus a trial.
• Windows File Recovery is a free Windows-only option from the Microsoft Store.

Verdict

GNU ddrescue is the right choice for advanced users who need dependable, restartable imaging from failing media at no software cost. Its mapfile-driven automation and broad device support are the main reasons to choose it. Look elsewhere if you need a guided graphical interface, simpler file undelete or a workflow that avoids POSIX command-line recovery.