Aura
Aura vs dupeGuru vs Czkawka vs AllDup
Which duplicate finder should you use for a photo and video library, or a whole drive? A comparison written by Aura's developer, so read it knowing that. Where a free tool is the better choice for you, this page says so.
The short version.
If you only need exact duplicates, all four tools work and Aura's free tier is as good as any. Pick whichever interface you like.
If you need similar photos (resized, re-edited, screenshots, bursts) or similar videos, and you care that nothing is uploaded, Aura Pro is built for exactly that. Czkawka is the best of the free tools for similar images, but it is a power-user tool: no quality ranking, no guided cleanup, no recycle folder with restore, and no way to run it on a server and use it from another machine.
Feature comparison
Checked against each tool's own documentation in September 2026. Tools change; if something below is out of date, tell me and I'll fix it.
| Feature | Aura | Czkawka | dupeGuru | AllDup | Duplicate Cleaner Pro |
|---|---|---|---|---|---|
| Exact duplicates, any file type | Free | Free | Free | Free | Paid |
| Similar photos (resized, edited, re-encoded) | Pro | Yes | Yes, fuzzy | Yes | Yes |
| Similar videos | Pro | Yes | No | No | Yes |
| RAW formats (CR2, CR3, NEF, ARW, DNG) | Yes, embedded previews | Partial | Limited | Limited | Yes |
| Pick the best copy automatically | Smart Select, quality ranking | Rules based | Rules based | Rules based | Selection assistant |
| Refuses to delete the last copy in a group | Always | Depends on selection | Reference folder | Depends on selection | Depends on selection |
| Run on a server or NAS box, use from any browser | Yes, Windows service with tray icon, Linux systemd | No | No | No | No |
| Recycle folder with restore | 14 days, built in | System trash | System trash | System trash | System trash |
| Network shares and large libraries | Tested to 38 TB on NFS | Fast, Rust | Slow on large sets | Windows only | Windows only |
| Open source | No | Yes | Yes | No | No |
| Windows | Yes | Yes | Yes | Yes | Yes |
| Linux | Yes | Yes | Yes | No | No |
| macOS | Planned | Yes | Yes | No | No |
| Android and iOS | Yes, same engine | No | No | No | No |
| Uploads your files anywhere | Never | Never | Never | Never | Never |
| Price | Free, Pro $7.99 once | Free | Free | Free, donation | About $30 to $40 |
When to pick each one
Pick Czkawka if
You want open source and you're comfortable doing the judgement yourself. It is fast and it finds similar images and videos. What it doesn't do: rank the copies by quality and pick the keeper for you, guide a non-technical user through a cleanup, keep deleted files restorable for a set period, or run on a server so you can clean the NAS from a laptop. Its similar-video matching is also coarser than Aura's frame fingerprints. If you're happy with a desktop tool and manual selection, it costs nothing and does the job.
Pick dupeGuru if
You want a simple, well-known open source tool for exact and fuzzy photo matching and your library is small to medium. It has been around a long time and is easy to install. It does not detect similar videos and it slows down on very large collections.
Pick AllDup if
You're on Windows only and want a free, mature tool with a lot of options. It is thorough for exact matches. Its similar-image mode is basic and there is no video similarity or Linux version.
Pick Duplicate Cleaner Pro if
You're on Windows, want a polished commercial product, and are happy paying more for a broader feature set including audio and document deduping. It is a good tool. Aura costs a quarter of the price and adds Linux and phones, but has a narrower focus on photos and videos.
Pick Aura if
Your problem is mostly photos and videos, your library is large or lives on a NAS, you want similar videos as well as similar photos, and you want the tool to choose the best copy for you and refuse to do anything irreversible. It is the only one here that runs as a service on a Windows or Linux box and is used from a browser on any device, and the only one with the same engine on your phone. Everything runs on your own hardware, and Pro is a one-time $7.99.
What Aura does not do
Being fair means listing the gaps too.
Not open source. It is a one-person project funded by one-time purchases. The privacy claim is verifiable another way: run it behind a proxy and watch nothing leave.
No macOS build yet. Notarization is planned. Windows and Linux are supported today.
Similarity is for photos and videos only. Exact-duplicate matching works on any file type, so it will find identical documents, music and archives. But it won't tell you that two songs or two PDFs are nearly the same. Duplicate Cleaner Pro does audio similarity; none of the others do.
The Windows installer is not yet code-signed, so SmartScreen shows a warning on first run.
Try it on one folder
The free tier finds exact duplicates with no signup and no time limit. Point it at one old shoot folder and compare the results with whatever you use today.