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DupEx
Find and remove duplicate files on Linux — safely, and fast.
DupEx (Duplicate Exterminator) is a high-performance tool for Linux that finds byte-identical files and helps you choose which ones to remove — fast, and without putting your data at risk. It does one thing, and does it perfectly.
Built for the one use case where getting it wrong is not an option.
- Never deletes without your knowledge
- No ads, no spyware, no tracking
- One-time purchase, no subscription
- Multilingual
- Native Linux app
Highlights
Safety by architecture
DupEx never deletes without your knowledge. Reference folders are automatically protected, auto-select never selects every file in a group, and before deleting you see exactly which files are affected — with a warning if a group would lose its last copy.
Optional byte-for-byte verification
By default a full-file BLAKE3 hash identifies duplicates. Turn on byte-for-byte verification and every match is confirmed bit by bit — so a hash collision can never cause a wrong deletion, not even in theory.
Fast funnel algorithm
Files are filtered in stages — group by size, sample hash, pairwise sampling, full hash — so the expensive reads only ever touch a handful of candidates. AVX2/SSE4.1 SIMD across all CPU cores via OpenMP. It started as an AVX2 byte-comparison in assembly; everything else grew around it.
Group & reference system
Compare your backup against the original without reporting the duplicates inside the backup itself. Hardly any other duplicate tool does this.
Automatic tuning
A lightweight pre-scan detects your storage medium (SSD / HDD / NAS), file-size distribution and available RAM, and tunes all scan parameters automatically — no manual tuning needed.
Real-time results
Duplicate groups appear while the scan is still running, sorted by path, name, type or size. You can review, select and even delete part of the results before the scan finishes.
Rule-based selection
Select oldest, keep the shortest path, filter by regex — DupEx selects thousands of duplicates in seconds, by your rules, then move them to the trash or delete them permanently.
Right from your file manager
Right-click any folder in Nemo, Nautilus, Dolphin, Caja or Thunar and scan it with DupEx — across Cinnamon, GNOME, KDE, MATE and XFCE.
Built for power users
Log levels, I/O tuning, memory-mapping control, a database hash cache (alongside the system cache) and extended thread statistics. Handles files well beyond 2 GB — with no unsafe code, no compiler warnings, Valgrind-checked.
Screenshots
DupEx ships with both a light and a dark theme — toggle to preview either. Click any screenshot to enlarge.
Editions & pricing
Launch offer — 20% off every edition through 31 July 2026.
Single license
1 license (one device)
Standard
3 licenses (one per device)
Pro
5 licenses (one per device)
All prices in EUR and include any applicable tax. The exact tax for your country is calculated and shown at checkout by Lemon Squeezy, our Merchant of Record and the seller of record. Business customers can enter a VAT ID at checkout.
Full version: one-time purchase, no subscription, no ads, no spyware — internet is only needed to unlock the full version.
Included in every paid edition
- Full-speed scanning across all CPU cores
- Move duplicates to the trash or delete them permanently
- Reference & protected folders plus keep-rules
- Automatic tuning for SSD, HDD and NAS
- Light and dark theme
- One-time purchase — no subscription
Free demo
Scan, find and inspect all duplicates and see how much space you could free — full speed, no limits. Deleting files is reserved for the paid editions.
Coming soonFrequently asked questions
Which Linux systems does DupEx run on?
DupEx runs on current 64-bit Linux desktops with GTK 4.12 or newer — for example Debian 13, Linux Mint 22, Ubuntu 24.04 LTS, Fedora 40, Arch Linux and openSUSE Tumbleweed. It also integrates a right-click action into Nemo, Nautilus, Dolphin, Caja and Thunar.
Can DupEx delete the wrong file by accident?
DupEx never deletes without your knowledge: reference folders are protected, auto-select never selects every file in a group, and before deleting you are warned if a group would lose its last copy. For absolute certainty you can enable byte-for-byte verification, which confirms every match bit by bit.
Is this a one-time purchase or a subscription?
A one-time purchase. There is no subscription and no recurring fee.
What is the difference between the editions?
Only the number of licenses: Single-Seat = 1, Standard = 3, Pro = 5, and Business for 25+ seats. The feature set is identical across all paid editions.
Does the free demo have any limits?
No limits on scanning: the demo finds and inspects all duplicates at full speed. Only deleting files is reserved for the paid editions.
Does DupEx need an internet connection? Is my data private?
DupEx runs locally and works offline; an internet connection is only needed to unlock the full version. No ads, no spyware — your files and their contents never leave your computer.
Can I get a refund?
Yes — see our Refund Policy in the footer for the conditions.
System requirements
DupEx runs on 64-bit Linux with GTK 4.12 or newer — most 2024-and-later distributions. It integrates a right-click action into your file manager, so you can start a scan straight from a folder.
- Operating system: 64-bit Linux (x86-64)
- GTK 4.12 or newer required (package libgtk-4-1) — included on the distributions below
- Runs on Debian 13 (Trixie), Linux Mint 22 (Wilma), Ubuntu 24.04 LTS (Noble Numbat), Fedora 40, Arch Linux, openSUSE Tumbleweed and others
- Desktop integration: right-click action in Nemo, Nautilus, Dolphin, Caja and Thunar (Cinnamon, GNOME, KDE, MATE, XFCE)
- Processor: 64-bit x86-64 with SSE4.1 (present in virtually all CPUs since ~2010); AVX2 acceleration is used automatically when available
- Memory: scales to available RAM, with a dedicated Low-RAM profile for small machines
- Storage: local SSDs and HDDs, external drives and network shares (NAS) are supported
- Internet: required only to unlock the full version