How to Use the Apple Photos Duplicates Album (And Why It Misses Most of Them)

The Apple Photos Duplicates album is a genuinely useful addition that Apple quietly introduced in macOS Ventura and iOS 16 — but it only catches a narrow slice of your actual duplicate photos. If you have ever merged everything it offered and then wondered why your library still feels bloated, you are not imagining things. Here is exactly how the feature works, where it falls short, and what you can do about the rest.

What the Photos Duplicates Album Actually Does

Apple's Photos app maintains an internal index of every image and video in your library. Starting with macOS 13 Ventura, the app compares files using a perceptual hash — a fingerprint derived from the actual pixel content of the image, not just its filename or file size. When two items produce an identical or near-identical hash, Photos groups them in the Duplicates album found in the sidebar under Utilities.

The key word is identical. The algorithm is tuned to catch exact duplicates and only the most obvious near-duplicates — images that differ only by EXIF metadata or minor compression artifacts introduced during re-import. In practice, this means Photos will surface the same photo imported twice from iCloud and from a camera card. It will not surface a burst shot where you kept two frames, a screenshot alongside a saved copy of the same image, or an edited version sitting next to its original.

How to Find and Merge Duplicates in the Photos App

If you have not used the feature yet, the workflow is straightforward.

1. Open Photos on your Mac.
2. In the sidebar, scroll to Utilities and click Duplicates. If the section is missing, your library may still be indexing — leave Photos open for an hour and check again.
3. Photos groups duplicates in pairs or small clusters. Each group shows the items side by side with their file sizes and dates.
4. Click Merge on a group to keep the highest-quality version and move the others to the Recently Deleted album. You can also click Merge All at the top to process every group at once.
5. After merging, open the Recently Deleted album and click Delete All to permanently remove the files and reclaim disk space. This step is permanent — deleted items are gone after 30 days regardless, but emptying immediately frees the space now.

Important: Merging is not reversible once you empty Recently Deleted. If you are uncertain about a pair, inspect them individually before merging. Zoom in to check for differences in crop, sharpness, or exposure before committing.

Where the Duplicates Album Falls Short

The built-in tool covers one scenario well — byte-for-byte or near-byte duplicates of the same file. A large category of real-world duplicates falls outside its detection window.

What slips through the Duplicates folder in Photos

• Burst photos. A 10-frame burst produces 10 distinct images. If you kept two frames that look nearly identical to the human eye, Photos treats them as separate intentional choices and will not flag them.
• Screenshots and saved images. A screenshot of a photo alongside the original photo share subject matter but differ in resolution and color profile, so the hash does not match.
• Edited vs. original versions. Photos stores the original and the edited version separately. The algorithm does not treat these as duplicates because technically they are not — but they still occupy double the space.
• Re-exported and re-imported files. If you exported a photo, ran it through Lightroom, and re-imported it, the pixel hash will differ enough to evade detection.
• Videos encoded at different bitrates. The same video exported at 1080p and 4K will not match.
• Files outside the Photos library. The Duplicates album only sees what is inside ~/Pictures/Photos Library.photoslibrary. Any photos living in Downloads, on your Desktop, or scattered across other folders are invisible to it.

Where Does Photos Actually Store Your Files?

Understanding the storage layout helps you decide what is safe to clean and what is not.

Your Photos library is a single macOS package at:

~/Pictures/Photos Library.photoslibrary

Right-click it in Finder and choose Show Package Contents to see inside. The originals live under:

~/Pictures/Photos Library.photoslibrary/originals/

Thumbnails and derivatives are cached separately:

~/Pictures/Photos Library.photoslibrary/resources/derivatives/

To see how large your library is from the Terminal:

du -sh ~/Pictures/Photos\ Library.photoslibrary

Do not manually delete files inside the package. Photos maintains its own database that maps filenames to metadata — removing files by hand corrupts that database and can cause the app to crash or silently lose images. Always use the Photos UI, or a tool that understands the library format, to remove content.

The Gap: Near-Duplicates That Live Outside Photos

The messiest duplicates are usually the ones scattered across your Mac — not inside the library at all. These are the photos you saved to Downloads before importing, the screenshots you took to share via Messages, the wallpapers you grabbed and then forgot, the RAW files sitting in a folder next to their JPEG exports.

This is where a file-level duplicate finder earns its place alongside the Photos tool. Crumb scans across your entire drive — not just inside a library package — and surfaces files that are identical in content regardless of filename, location, or the app they belong to. It can find that 12 MB HEIC you imported into Photos still sitting in your Downloads folder from two years ago, or the same vacation video exported to three different directories.

The comparison table below shows the difference in scope between the two approaches.

A Practical Workflow for Cleaning Up Photos Clutter

1. Run the Photos Duplicates album first. Merge what Photos finds. This handles the easy, obvious cases cleanly and safely within the app's own database.
2. Empty Recently Deleted to actually reclaim the space — merging alone does not free disk space immediately.
3. Scan your whole Mac for file-level duplicates. Use a tool like Crumb to find copies of images and videos that exist both inside and outside your Photos library, or spread across multiple locations on disk. Review each group carefully before deleting — a file that looks like a duplicate might be your only backup copy.
4. Check your Downloads and Desktop folders. These are the most common landing zones for accidental photo copies. Sort by file type (.heic, .jpg, .mov) to spot media files quickly.
5. Do not touch the Photos library package contents directly. Only delete files through the Photos UI or a tool that explicitly supports Photos library cleanup. Manual deletion inside the package is not safe.

Is It Safe to Delete What the Duplicates Album Suggests?

For items that Photos flags as duplicates, the merge operation is safe in the sense that Photos retains the highest-resolution version and preserves all metadata. However, "safe" assumes your library is healthy and fully backed up before you start. Always verify that Time Machine (or your backup of choice) has a recent snapshot of ~/Pictures/Photos Library.photoslibrary before doing a large batch merge. If your library has previously encountered errors, run File > Repair Library first.

For duplicates found outside the Photos library — loose files on disk — deletion is permanent and there is no undo. Check each item before removing it, especially if you are not certain whether the copy inside Photos is the full-quality original or a compressed export.

Conclusion

The Apple Photos Duplicates album is a solid starting point, but its scope is deliberately narrow: exact and near-exact matches inside your library only. Most Mac users have years of photo clutter scattered well beyond that boundary — in Downloads, on external drives, inside old backups, and across project folders. Treating the two layers separately — the in-library merge tool for what Photos can see, and a whole-disk duplicate finder for everything else — is the most thorough way to recover meaningful space without risking data you actually want to keep.