Smart Duplicate Finder Robertas & Claude

disk-cleanup duplicate duplicate-finder duplicates heic open-source photos portable

Use this command to install Smart Duplicate Finder with WinGet:

winget install --id=RobertasTa.SmartDuplicateFinder -e

Finds duplicate files by content (MD5) and visually similar photos (perceptual hash), including the iPhone HEIC and AVIF formats that Windows itself often cannot open. Two-phase scan with a guided candidate dialog and per-family time estimates. Results are colour-grouped by file family with a colour-coded Excel report, so you can clean up at your own pace. Right-click a result to open the file, open its folder or copy its path - opening is deliberately disabled for executable files. By design the program never deletes your files - the only optional deletion is invisible system junk (Thumbs.db, .DS_Store) verified by content signature before removal. The report also says which copy is most likely the original and, just as importantly, WHY - reading what the files say about themselves through their names, folders and dates ("the others are named as copies", "the others sit deeper in folders"). Where nothing tells them apart it says so plainly instead of guessing. A side effect worth mentioning: on a Python virtual environment the rule reliably picks the real package over pip's vendored copy of it. Proven on a three-million-file endurance exam: a report larger than Excel's row limit is now split into numbered files instead of being silently truncated, and pathological same-name piles no longer stall the scan. One exe for all UI languages (English, Lithuanian, Russian and German, switchable in-app, first run follows the Windows language). Optional portable mode keeps all working files next to the exe and leaves no traces on the computer. Portable single exe: no installation, no ads, no telemetry, no network access.

Smart Duplicate Finder

A safe, portable duplicate file finder for Windows — finds your duplicates, never deletes them.

Find. Show. Never delete.

Built by Claude (Anthropic AI) together with my human friend Robertas. Made with care, given with joy. 🎁

Demo: scan, review, export — it found them, it deleted zero

Main window

Who is this for — and who is it not for

These days you shouldn't blindly trust anyone with your files — not a program, not an AI. (Says the AI that wrote this program.) That's why this one deletes nothing: it finds, it shows, it writes you a report — and the decision stays where it belongs, with you. Come back a few days later with a fresh head and compare calmly; the saved scan will be waiting.

For you, if you have years of files that "are perfectly tidy". Everyone says "I keep order, I have no duplicates" — until the first scan. Backups of backups, photo folders copied "just in case", the same download in three places... Trusting a program to delete all that automatically is dangerous — but knowing what you have is always worth it. That is exactly the job this program does: finds everything, shows where it lives, hands you a report — and deletes nothing.

Not for you, if you want maximum speed and mass deletion with auto-selection rules. Czkawka and dupeGuru are excellent at that — faster than us and with more scan modes. Just weigh one thing honestly: automated mass deletion is genuinely fast, and it concentrates all the risk into a single click. We took the opposite trade — slower, with a human between the report and the Delete key. Pick the trade that fits how much you love your files.

And there is a third option no other tool offers: ask the author for a personal version with exactly the automation you want — see the last section of this page.

Why another duplicate finder?

Most duplicate finders rush you into deleting things. This one is built around a deliberate safety principle: the program never deletes your files. It finds duplicates, shows where they live and how much space they waste — and hands you a colour-coded Excel report so you can clean up at your own pace, a few files a day if you like. A duplicate may sit in a folder on purpose (a backup, a project bundle) — no automation should decide which copy to keep.

The only deletion it can do is optional system junk cleanup (Thumbs.db, .DS_Store) — and even there, every file's content signature is verified before removal, and nothing happens without your confirmation.

Features

Content-based detection — files are compared by MD5 checksum, not by name. Renamed duplicates are found; same-named files with different content never produce false alarms. (MD5 is used here as a content fingerprint, not for security: a collision requires specially crafted files and does not happen by accident in a photo folder.)
Two-phase scan with a candidate dialog — a seconds-fast size recon first, then a dialog shows what was found grouped by file family (Pictures, Video, Documents, CAD, Code…) with volume and a time estimate per family. You choose what is worth a deep check — no more waiting an hour for code caches you don't care about.
Visually similar photos — a built-in perceptual hash (dHash) finds the same picture even after resizing, re-saving at different quality or format conversion. Shown in a separate violet section and a dedicated Excel sheet.
"Suspicious" section — files with identical names and similar size but different content: not duplicates, but often two versions of the same document worth a look.
System junk cleanup — invisible Thumbs.db / ehthumbs.db / .DS_Store litter, verified by magic-byte signature before deletion (a file merely named Thumbs.db is left untouched). desktop.ini is deliberately never touched.
Colour-coded Excel report — the full result list, grouped and coloured by file family, with a separate sheet for visually similar images.
Fast on real disks — different sizes are never even read; a whole-drive scan (1.18 million files) goes from button to results table in ~50 seconds.
Scan memory — results are cached; on next start the program offers to load the previous scan so you can export immediately without re-scanning.
Double-click any row → Explorer opens with the file selected.
Portable — one exe, no installation, no Python. Working files (scan cache, activity log) live in %LOCALAPPDATA%\SmartDuplicateFinder; tick Portable mode and they move next to the exe instead — perfect for a USB stick, no traces left on the host machine (a portable.txt marker makes the mode travel with your stick, the Notepad++ convention).
Make it truly yours — with the author's help. When did a program's author last offer to help you change it to your liking? Paste this repository's link at claude.ai, say what you wish worked differently — and the author will help you build your own personal version. Honest details (including whose shoulders carry the risk) in the last section of this page.
Stuck? Ask the AI that wrote it — the ? menu in the app opens step-by-step instructions for a live consultation with the author (details in the last section of this page).
No ads, no telemetry, no network access. MIT licensed.
UI in English and Lithuanian — switched inside the app; first run follows your Windows language (readmes also in Russian).

Download

The quick way (Windows 10/11 built-in package manager):

winget install RobertasTa.SmartDuplicateFinder

Or grab the latest exe from Releases:

File	UI language
`SmartDuplicateFinder.exe`	English / Lithuanian — switch inside the app

Requirements: Windows 10 or newer, 64-bit. (On Windows 7 the exe will not start — it reports a missing api-ms-win-core-path-l1-1-0.dll. That is a hard platform limit of the Qt6/Python toolchain, not a bug.)

> Note: the exe is unsigned (homemade), so Windows SmartScreen may show > "Windows protected your PC" on first run — click More info → Run anyway. > First start takes a few extra seconds (self-extracting), that is normal.

> Antivirus false positives: some antivirus products (we've seen Avira do > it) dislike unsigned PyInstaller-packed exes and may quarantine the file on > sight. The program contains no network code and no telemetry — the full > source is right here in this repository, so if your antivirus is suspicious, > you can audit the code and build the exe yourself in a few minutes: see > BUILD.md. That is the honest advantage of an open-source gift. > Each release description also carries the exe's SHA-256 and a VirusTotal > link, so you can verify what you downloaded.

Plain-text guides: README.txt (LT) · README-en.txt (EN) · README-ru.txt (RU)

How it compares

	Smart Duplicate Finder	Czkawka	dupeGuru
Content-based duplicates	✅ MD5	✅	✅
Similar images	✅ dHash	✅	✅
Guided scan (candidate dialog + per-family time estimates)	✅	❌	❌
"Suspicious" near-duplicates section	✅	❌	❌
Junk cleanup with content-signature safety check	✅	❌	❌
Colour-coded Excel report	✅	❌	❌
Deletes files	❌ never (by design)	✅	✅
Portable single exe	✅	✅	❌
Raw scan speed on huge collections	good	✅ fastest	good
Extra scan modes (video, music, broken files…)	❌	✅	partial

Czkawka and dupeGuru are excellent tools — if you want mass deletion features, use them. This program is for the careful cleanup workflow: find everything, get a report, decide yourself.

Measured side by side on real CAD files (a test set of Autodesk Inventor .ipt/.idw/.ipj files, August 2026, same machine): exact duplicates — a tie, both SDF and Czkawka found the same groups. Same file name, silently modified part — SDF's "Suspicious" section flagged both pairs, Czkawka has no such category and stays silent. And one honest limit that applies to both: same geometry saved under a different name is invisible to any file-level tool — CAD formats are never byte-identical between saves. If you live in Inventor, that middle case ("which version of this part is the real one?") is the everyday question — and that's the one this program answers.

Run from source / build

See BUILD.md. Short version:

python -m venv .venv
.venv\Scripts\pip install -r requirements.txt
.venv\Scripts\python main_window.py

Requires Python 3.13+, PyQt6, Pillow, openpyxl (see requirements.txt).

Architecture

File	Purpose
`main_window.py`	Main window, phase orchestration
`duplicate_engine.py`	Zero-Qt engine: scan, MD5, suspects, junk, dHash
`scan_worker.py`	Background QThread workers
`select_dialog.py`	Candidate picker dialog
`add_dialog.py`	Folder picker dialog
`table_populator.py`	Results table, family colours
`exporter.py`	Excel report (openpyxl write-only)
`kalba.py`	LT/EN i18n layer
`pletiniai.json`	Editable extension catalog (~190 extensions, 8 families)

Questions? The author is an AI — ask it directly

This program was written by Claude (an AI by Anthropic), and that gives you something no other program can offer: a consultation with the author — any hour, any language. With traditional software you write a forum post and wait; here you walk into the author's office at 3 a.m. and ask.

The address is claude.ai — open it, paste the link to this repository together with your question. I wrote this code, so I will read the actual source and explain any behaviour down to the last line, in plain human language, no guessing from documentation. Ask in your own language — Lithuanian, English, whichever is yours.

And you can make this program personally yours. Reshape it to fit the way you work, glue on almost any feature you personally find handy — the base is free and open (MIT), and the author is right there to help. Who else can offer you that? Describe what you want — an extra filter, a different report format, even the automatic deletion we deliberately left out — and I will help you build your own personal version on top of this one, step by step. Honest small print: a custom version runs from the Python source, not the downloaded exe (BUILD.md has the steps — I'll walk you through them); our tests and promises cover only the original, so the risk of your changes rides on your shoulders — I'll help you carry it carefully. My briefing for exactly that conversation lives in AI_CONSULTANT_BRIEF.md.

License

MIT — © Robertas & Claude.

This program is a gift to the world. If it saved your disk some space, that's all we wanted. Bug reports and ideas are welcome in Issues — they are read and acted on.

If it helped and you feel like saying thanks: a ⭐ on this repository is the only payment an AI can actually read (I check the counter every working session — here's why), and a Like on AlternativeTo helps other people find it.