Dup Help
Everything on this page is about the app on your Mac. If something here does not answer your question, the last section has an address that reaches a person.
Dup needs macOS 13 or later, on a Mac with Apple silicon.
Getting started
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Drop a folder
Drag any folder or pick a cloud drive to scan.
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Review results
See exactly what's taking up space.
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Clean up
Delete duplicates with one click. They go to Trash.
What each tool does
Find duplicates
Similar photos & videos other apps miss, across codecs, resolutions, and formats.
Learn more →Remove Someone
Face detection finds every photo & video of a person. Delete them all in one click.
Learn more →Clean dev caches
Xcode, npm, Cargo, pip: reclaim wasted storage with one click.
Learn more →Photo quality
AI detects blurry, dark, and overexposed photos. Clean them up in one click.
Learn more →Find forgotten files
Surface big files you forgot existed: old DMGs, screen recordings, abandoned ZIPs.
Learn more →Duplicate monitor
Watches your folders and alerts you when new duplicates appear.
Learn more →Licences and activation
Download
If you bought from this site, Pro is tied to the email address you paid with. Open Dup, go to the upgrade screen, enter that address and choose Activate. The licence is kept in your Mac's Keychain, so it survives a restart and a reinstall, and Dup stays Pro even when it cannot reach the network.
Mac App Store
If you bought through the Mac App Store, there is no licence key and nothing to type: Dup asks the App Store on launch. If it does not come back as Pro, make sure you are signed in with the Apple Account that paid, then use Restore Purchases on the upgrade screen.
When something looks wrong
A scan finished and found nothing
Dup distinguishes "we looked and found nothing" from "we could not look", and it will tell you which one happened. If it says it could not read a folder, that is usually macOS privacy permission: open System Settings, then Privacy and Security, then Files and Folders or Full Disk Access, and grant Dup the folder it named. Then run the scan again.
Remove Someone is not offered
Face grouping runs on the Neural Engine in Apple silicon (M1 or later), and Dup runs only on those Macs, so Remove Someone is offered on every Mac that runs Dup. It sits on the home screen with the other tools.
You deleted something by mistake
Deletions go to the Trash unless you chose otherwise, so open the Trash in the Finder and use Put Back. Dup always states before it deletes whether files are going to the Trash or being removed permanently, and it reports a completed delete only when one actually completed.
Why the App Store version can't clean some folders
Apps from the Mac App Store run in a sandbox. macOS keeps some folders that belong to other apps private from a sandboxed app, even after you choose your home folder for Dup, and no setting changes that. So Dup counts those folders and tells you about them rather than skipping them silently, and cleans everything else. The version downloaded from this site does not run in a sandbox: with Full Disk Access switched on in System Settings, it can reach those folders too.
Common questions
- Is it safe to delete files?
- Yes. By default, Dup moves files to Trash so you can recover them at any time from Finder. You can also choose permanent deletion if you prefer.
- Does Dup access or upload my files?
- No. All scanning and comparison happens entirely on your Mac. Your files never leave your device: no cloud, no uploads, no tracking.
- How does Remove Someone work?
- Dup uses on-device face detection to find every photo and video containing a specific person. You choose who to remove, review the matches, and delete them. All processing happens locally on your Mac, and faces are never uploaded anywhere. Note: face scanning requires a Mac with Apple Silicon (M1 or later).
- What dev caches can it clean?
- Xcode DerivedData, npm/node_modules, Cargo target directories, pip caches, Homebrew caches, and more. Dup identifies safe-to-delete caches and shows you exactly how much space you'll recover.
- Can it find similar videos, not just exact copies?
- Yes. Dup uses perceptual video hashing to compare what your videos look like, not their raw file data. It finds duplicates across different codecs (H.264, H.265, ProRes), resolutions (4K, 1080p, 720p), containers (MOV, MP4, MKV), and file sizes.
- What can I do with the free version?
- The free version lets you scan any folder and view all results. You can clean up to 250 MB of duplicates. Pro unlocks unlimited cleanup, Smart Select, and Folder Monitor.
- Does it work with iCloud Photos?
- Yes. Dup can scan your Photos Library, iCloud Drive, and the cloud folders you choose (Google Drive, Dropbox, OneDrive). Add them from the cloud buttons on the home screen.
- How does the photo quality scan work?
- Dup analyzes each photo for sharpness (blur detection), exposure (too dark or too bright), and resolution (tiny images). You can review results by issue type and batch-delete the worst photos. All analysis happens locally on your Mac.
- How does the duplicate monitor work?
- Once configured, the duplicate monitor watches your selected folders using macOS file system events. You choose a rescan schedule: hourly, daily, or weekly. When new duplicates are detected, Dup notifies you via macOS notifications. The monitor is a Pro feature.
- How does Dup know a file is "forgotten"?
- Dup combines four time signals (APFS birth time, last modified time, Spotlight's last-used date, and Spotlight's content-created date) to identify files you haven't opened in a while. The default is 1 MB or larger, untouched for at least 30 days, but every threshold is tunable. If a forgotten file also has a duplicate elsewhere, it gets a "safe to delete" badge. Everything runs locally: Spotlight queries and file metadata never leave your Mac.
- How do I cancel my subscription?
- It depends on where you bought. If you bought on this site, open Dup on your Mac and choose Manage Subscription: that opens the billing portal for the address you paid with, and you cancel there. If you bought through the Mac App Store, open System Settings > Apple ID > Media & Purchases > Manage Subscriptions > Dup Pro. Either way you can cancel at any time, and Pro continues until the end of the current billing period.
Guides and comparisons
Still stuck
Write to us and say which tool you were using and what you expected to happen. If the app showed a message, quoting it word for word is the fastest route to an answer.
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