Cisdem Duplicate Finder vs Dup Detector

Cisdem Duplicate Finder detects duplicate files and visually similar photos on macOS and Windows. It compares file contents rather than filenames, covering images, documents, songs, videos, archives, and duplicate folders. For photos, it can identify burst shots, edited or resized versions, and pictures taken from different angles or in different lighting. The maker says this photo analysis runs entirely on the device without uploading files to a cloud or server. Results can be previewed in three modes, then sorted, searched, and filtered. Users can remove duplicates permanently, move them to Recycle Bin or Trash, or place them in a selected folder. Supported locations and services include external drives and SD cards, iTunes and Apple Music, Mac Photos, OneDrive, Dropbox, Google Drive, and iCloud. The trial can scan, preview, locate, and hide duplicates, but cannot delete all selected duplicates with one click. One-time individual licenses cost $39.99 as a one-time purchase for one Mac or one PC; one-year subscriptions cost $19.99 a year. Business licenses cost $54.99 as a one-time purchase for one computer.

Dup Detector is a free, open-source desktop application for finding duplicate files and reclaiming storage space. It runs on Linux, macOS, and Windows. Smart hashing compares file sizes first, then partial content, and performs full content hashing when needed. The maker says smart hashing can scan 10,000 or more files per second. Multithreaded scanning is supported, and the app describes its memory footprint as minimal. Dup Detector identifies duplicates but does not remove them automatically, so users decide which files to keep or delete. The maker says the code is fully open source and welcomes inspection and contributions. It states that the app has no analytics, telemetry, or data collection. The Free plan costs nothing, is available forever, and includes cross-platform use. GitHub issues and Discord provide support and feedback channels.