128,460
files inventoried
DeDuck finds the duplicate and near-identical files clogging your drives and NAS, then tidies everything into one clean master library — without ever modifying your originals.
Inventory before action · Originals are immutable · Every operation is logged
Friendly on the surface, ruthless about clutter underneath. Its one job is to bring order — leading your files into a single clean row, never hoarding them.
Finds and gathers scattered files across drives, folders and NAS — walking each once, then rescanning incrementally.
Spots exact and look-alike copies through five escalating levels of matching — from file size all the way to perceptual similarity.
Places everything in order — a curated master library, sorted by media year, type or folder, with identical files stored once.
Leaves you with everything in line: a clean, duplicate-free row you can trust — and a full report of what changed.
DeDuck inventories, understands, preserves and organizes everything across external drives and NAS devices — with cloud connectors on the roadmap.
Finds mounted volumes and recognizes the same physical drive across remounts. Add any folder or NAS mount as a scannable root.
Walks a drive once and records every file, built to handle millions with batched, resumable writes. Rescans skip unchanged files and flag vanished ones.
incremental · resumableFive escalating levels — size, xxHash quick hash, SHA-256 confirmation, media verification and perceptual similarity for near-identical images.
5 levelsChoose the copy to keep — newest, oldest or shortest path — preview the exact plan, then move to Trash, Quarantine (undoable) or delete. A group is never left without a copy.
preview firstMatch two folders by content — Matched, A-only, B-only and Conflicts — then reconcile: Make A = B, or fill one from the other. Every copy is additive; nothing is moved or overwritten.
matched by hashDimensions, camera make and model, capture time, GPS and a perceptual hash — degrading gracefully when the media extra isn't installed.
Evidence-based suggestions: reclaimable duplicate space, folders that live on only one drive, stale scans. Nothing destructive ever happens automatically.
Totals, category breakdown, largest folders and scan history — in a simple native window or straight from the command line.
Build one or several curated libraries (DDL<n>) — originals stay put, identical files stored once. Organize by type, year/month or flat, and merge libraries into one.
Tag folders Master / Onsite / Offsite and check coverage — matched by content hash, so it counts even if a backup renamed the file. See exactly which files still need a second (or offsite) copy.
3 copies · 2 media · 1 offsiteEvery file is re-hashed right before it's touched, every action is written to an audit trail, and destructive steps always require explicit approval.
DeDuck escalates carefully — cheap checks first, cryptographic proof before any action. Only byte-identical groups are ever eligible for cleanup.
An instant first pass — files of different sizes can't be identical.
A fast, non-cryptographic fingerprint to narrow the field cheaply.
Cryptographic confirmation that two files really are byte-for-byte equal.
Validates decoded media so photos and videos are checked as media, not just bytes.
Finds near-identical images — resized, re-saved or lightly edited look-alikes.
The whole promise, in one motion: doubled, disordered files settling into a single clean line behind the duck.
DeDuck's core principles aren't a settings screen — they're how the engine is wired. Only Move to folder and Delete ever change an original, and both ask first.
Scanning and detection never write to your drives. Data lives only in DeDuck's own application-support folder.
See the exact cleanup plan — every file marked Keep, Moved or Deleted — before a single one is touched.
Cleanup moves duplicates to the Trash unless you choose otherwise. Permanent deletion is always double-confirmed.
Every file is re-hashed right before it's touched, and a duplicate group always keeps at least one copy.
Every action is written to a log and a CSV report — Name, Location, Size, Modified, Type, and Keep / Moved / Deleted.
This mirrors the in-app Help tab. DeDuck is read-only by default — your originals are never modified. Only Move to folder and Delete change originals, and both ask first.
1. Dedupe → Detect Dupes. DeDuck rescans, then finds byte-identical copies (Exact). Tick Include Similar Photos to also group visually-similar images (Similar; slower, needs the media extra). Exact and Similar never overlap.
2. Tick the copies to clean up — the keeper stays. “Show only ticked” narrows the view to the marked copies.
3. Clean up… → Move to Trash (reversible), Quarantine (undoable, restorable from Activity), or Delete permanently (double-confirmed).
4. A CSV report is written for every cleanup — Name, Location, Size, Modified, Type, and Keep / Moved / Deleted.
Safety: a group is never left without a copy, and each file is re-checked right before it's touched.
Pick two scanned folders (A and B) and Compare. DeDuck matches by content (hash), so a file counts as present even if it was renamed or moved.
A library is a DeDuck-owned folder (DDL<n>_<name>) holding an organized copy of your files — your originals are never touched. You can have several.
Tag each folder Master / Onsite backup / Offsite, then Check backup coverage. Aim for 3 copies, on 2 media, with 1 offsite.
scripts/backup_offsite.sh (rclone → cloud).Generate a shareable Digital Clutter Report — a tidiness grade, reclaimable space, what's using space by type, and your biggest duplicate groups — from Activity → Reports, the Library tab, or deduck clutter. Open it to Print / Save as PDF.
Duplicates (moved files), Reports (CSVs), and MasterLibrary (the curated copies).Nothing is written to your scanned drives.
~$…, *.tmp) are ignored automatically./) is discouraged — pick specific folders; the app warns you.python -m deduck serve) reached from other devices over Tailscale — see docs/DEPLOY-MACMINI.md. Cloud connectors (Immich, Google Photos, Lightroom) are on the roadmap.Desktop-first for macOS & Windows. Download the installer, scan a folder, and let the duck lead — or run it as a private web server on your own Mac mini.
macOS & Windows · v0.24 · fully offline · cloud connectors on the roadmap