--- title: "DuplicateDuster — Local File Deduplication" description: "Finds files and folders stored twice by comparing contents, not names, across all your drives. You choose which side may be cleaned. Nothing leaves the machine." url: "https://royalsoftworks.com/products/duplicate-duster/" source: "https://royalsoftworks.com" format: "markdown" note: "Markdown rendering of the HTML page at `url`. Same content, same canonical URL." --- [All products](https://royalsoftworks.com/#products) Finds files you saved twice # Find the copies. Keep one. Take your space back. You tell DuplicateDuster which folders hold the originals and which ones are allowed to lose files. It compares them byte for byte, shows you every exact copy — single files and whole folders — and only ever deletes from the side you pointed at. It runs on your own machine, and nothing is sent anywhere. [Get it free](https://royalsoftworks.com/download/#duplicate-duster) See it find them Windows · Linux to follow — free tier scans without limit · Pro is €20 once, VAT included A B C A D E F B G C H A I D J F K E L G M H B N Example scan · duplicates found 0 Space reclaimed 0.0 GB Exact-match certainty How it matches ## One method, and it's never wrong. DuplicateDuster hashes the actual content of every file with SHA-256. Two files with the same hash are byte-for-byte identical — there's no approximation, no scoring, and no false match. The filename never matters: a copy renamed or moved to a different folder is still recognised the moment its content matches. ### What it catches - Exact, byte-for-byte duplicates anywhere in the folders or drives you selected - Copies that were renamed — the match is on content, not the filename - Copies moved to a different folder or a different drive - Whole folders whose recursive contents are identical, reported as one finding - Any file type — hashing doesn't care what the file is ### What it doesn't - A file that was re-saved, re-encoded, or edited — even by one byte — won't match - There's no "similar image" or "near-duplicate" detection - Symbolic links are never followed and never reported — a tool that deletes files has no business resolving them - Zero-byte files are ignored: they all match each other, and removing them frees nothing We'd rather tell you the boundary than oversell it. Explore DuplicateDuster ## Exact matching, explained — and proven safe. What it catches, where it's used, and exactly what happens to a file before it's removed. - [Overview, continued You decide which side may lose files Sources hold what you keep, targets are what gets cleaned, and only the target side ever gets a checkbox. Then one real scan, start to finish.](https://royalsoftworks.com/products/duplicate-duster/two-sides/) - [Overview, continued Free and Pro Scanning is free and unlimited; Pro is €20 once and lifts the cap on each clean-up.](https://royalsoftworks.com/products/duplicate-duster/editions/) - [Features What it does SHA-256 matching for files and folders, four reclaim modes, filters, and what it deliberately doesn't claim.](https://royalsoftworks.com/products/duplicate-duster/features/) - [Use cases By scenario Creative archives, backups gone wild, shared drives and photo libraries.](https://royalsoftworks.com/products/duplicate-duster/use-cases/) - [How it works Scan to space reclaimed The size pre-pass, the worker pool, folder matching, and the four ways to reclaim.](https://royalsoftworks.com/products/duplicate-duster/how-it-works/) - [Security Nothing leaves the machine Local-only processing, protected system paths, and what secure erase really guarantees.](https://royalsoftworks.com/products/duplicate-duster/security/) - [Whitepaper Technical reference Matching model, threading, folder signatures, and the reclaim implementations, in detail.](https://royalsoftworks.com/products/duplicate-duster/whitepaper/) - [FAQ Common questions Source vs target, folder matches, free-tier limits, and how secure erase really works.](https://royalsoftworks.com/products/duplicate-duster/faq/)