Find duplicate photos on Apple Mac and delete them in Photos

It is easy to accidentally duplicate photos and waste space on the disk. You might even have several gigabytes worth clogging up the system. Use this utility to find them and delete them.

The more photos you have transferred to the Mac and added to the disk (SSD, disk, hybrid, whatever) and the more you have edited them, the more duplicates there will be on the system. Some people who have very large photo collections have found that the space occupied by duplicate images runs to over a gigabyte.

Finding and deleting duplicate photos might free up a lot of disk space. Many Mac owners cannot afford to waste space with duplicate files of images they already have elsewhere on the system. Drives of 128, 256 and even 512 GB are easily filled and duplicates are a wasteful and inefficient use of the storage space.

Search the Mac App Store for duplicate finders and there are several that can track down copies of photographs and let you remove them. Several of them are by the same developer and Systweak Software has Duplicate Photos Fixer, Photos Duplicate Cleaner, Duplicate Photos Fixer Pro, Duplicate Cleaner for iPhoto.

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It is very confusing and it is hard to know which one to go for. Some are free, others require payment. I bought Duplicate Photos Fixer Pro many years ago when it was on a massive discount and it cost me just US $0.99. That was a bargain because it is $19.99 these days, but you never know, maybe there will be another discount sale. Find the app in the Mac App Store. Try the free version if you like. It will find duplicates, but it will only let you delete 15 photos, so you really need the Pro version.

Duplicate Photos Fixer Pro

This app is able to search the Photos library, a folder of photos, or photos you add manually. Most likely, your photos will be in the Mac's Photos library and it works well with this and I used it with the macOS Big Sur version of iPhoto.

Duplicate Photos Fixer Pro Mac app

The app has some great fuzzy matching rules that find photos that are similar, but not exactly the same. You can set the matching level, which is how similar the images must be, using a slider. It shows two photo thumbnails that give you an idea of how similar the photos must be, which is very useful There is also a time interval and photos can have different times on them, but are still regarded as the same, and they may have similar, but not identical GPS coordinates.

Criteria used for matching photos

You can add your iPhoto or Photos library by clicking a button, but it is also possible to manually add photos and folders by dragging them from Finder.

Search options in Duplicate Photo Fixer Pro

There are options not scan photos only within a certain time period, such as today, yesterday, the last 7 or 15 days, last month or last year. This is useful if you just imported a collection of photos into iPhoto and it saves time by only checking recent photos and not the whole Photos library, which for some people is hundreds of gigabytes.

Scanning large photo libraries, we are talking tens of thousands of images, can take some time, so be patient.

Find and delete duplicates

While using this fuzzy matching I found several photos that were identical, but one was upside down. I have no idea how that happened and it might have been someone playing with photos apps on the iPad, which then got synced to the Mac. Anyway, Duplicate Photos Fixer Pro found them and it shows the sort of fuzzy matching that is possible. Another app might not have spotted these because they are not identical and they have different sizes and dates.

Mark the duplicate to delete

After scanning the Mac you might end up with hundreds of duplicate photos. You can go through them one by one and compare them. There are checkboxes so you can select the one to delete, but with a large Photos library, this could take hours or even days!

There is a shortcut and at the top of the window is there is an Auto Mark button. This uses rules to automatically select one of the duplicates to keep and to automatically mark the others for deletion.

The rules used to auto-select the appropriate image to delete can be configured in the app preferences. For example, if two photos are the same, but one is smaller then the smaller one is selected for deletion. The one with the oldest date, the newest date, the smaller DPI and so on, can all be auto-selected. You choose the rules and they can be dragged into the order you want.

The rules are good, but it is still worth going through the photos, even if you only skim and don’t spend too long. When you are happy you don't want the marked photos, the Trash Marked button deletes them.

The iPhoto connection

Well, actually it doesn't delete photos. It is quite clever and what happens is the app automatically opens the Photos app, marks the duplicate photos and moves them to a Duplicates album. This gives you another opportunity to check the photos and if you are happy with them, you can delete them in iPhoto. Remember that the Photos app has its own trash and keeps photos for up to 40 days after you delete them.

Overall, this is a very useful app for cleaning up photo collections. It is hard to accidentally delete anything you want to keep and there are opportunities to change your mind and recover them.

Title: Duplicate Photos Fixer Pro
Price: US $19.99
Developer: Systweak Software
Size: 38.6 MB
Version: 3.1
OS X: 10.7 or later
Verdict: An essential tool for keen photographers