jdupes

What jdupes is

jdupes is a free utility for locating and handling exact duplicate files on Linux, macOS, and Windows. It treats files as duplicates only when they are 100% identical, rather than matching similar images, sounds, or other file types. Matching can use file size, hashes, and full byte-by-byte comparison, with optional partial-hash matching. The project says it verifies matching data after hashing to reduce false matches caused by hash collisions. Actions include prompting before deletion, deleting without a prompt, linking duplicates, summarizing results, and copy-on-write deduplication. Linux and Unix instructions use one or more directory paths, and the project provides a native Windows port with support for Windows-specific behavior, including Unicode. Docker usage is documented, and standard output can be piped to shell scripts to process match sets. A hash database can store paths, hashes, and other metadata for repeat scans, but the project labels this feature under development and notes quirks. The README warns that quick matching skips byte-by-byte verification and may classify non-duplicates as duplicates. It also warns that disabling file-change checks creates a time-of-check-to-time-of-use security vulnerability, especially when linking or deleting files. jdupes is distributed under the MIT License.