At a glance

Once all duplicate images are detected you can preview the files and select what you want to remove. When satisfied with the scan results you can either manually select all the duplicates or can use Auto-Mark to select duplicate images from each group. This option keeps one copy from each group unchecked.

• Duplicate Photo Cleaner is the only software for managing duplicate and similar photos on Windows, Mac, and mobile phones you'll ever need. It's different from other duplicate photo finders because it compares photos just like a human would and detects similarities the smart way.
• May 02, 2020 Some of these duplicate file finders are really powerful, like Duplicate Searcher and CloneSpy, but the caveat is their dated interface and the requirement for manual work. While these are free, others like XYplorer and Duplicate Detective offer a much more seamless and hassle-free interface and operation at the expense of costing you big bucks.
• 1 day ago Duplicate File Detective 7.0.79. Automate the common tasks you have to perform on your computer, such as search or convert photos f. Apr 13th 2021, 09:19 GMT.

Our Verdict

As much as we love feature-packed applications that perform countless tasks, there’s nothing wrong with an inexpensive utility that does the one thing we need without much fuss and bother. Such is Fiplab’s $5 (currently on sale for $3) Duplicate Detective (Mac App Store link). As its name implies, it exists to locate duplicate files on your Mac and then, if you wish, fling them into the Trash.

Duplicate Detective does its work in a simple way. Just launch the application, and then drag a folder or volume into the utility’s window. Duplicate Detective scans that folder or volume, and then lets you know how many duplicates it finds. What it’s specifically looking for are exact duplicates by comparing each file’s hash strings. If the strings match up, you have a duplicate; if they don’t—if one file is a PNG version of an image and the other a JPEG—the files are not included in the duplicate tally.

If you have a lot of files—say, hundreds of thousands, as could easily be the case with a large hard drive—this can take a very long time. If you’d like a faster result, scan a folder rather than an entire volume. (In a nice touch, when performing lengthy scans, the application displays humorous messages along the lines of “So, how’s your day going?” to let you know that it hasn’t locked up.)

When the job’s done, you’ll see the number of files scanned, the duplicate count, and the amount of storage space the superfluous files consume (thus giving you an idea of the amount of space you’ll save if you delete the duplicates).

Click Next, and you’ll see a list of duplicate groups on the left side of the window. (Each group contains all the duplicate versions of a particular file.) You can filter this list, using buttons at the top of the window, to display only folders, images, docs, audio files, archives (for example, .zip, .hqx, and .sit files), apps, or others. Select an item in the list and, to the right, a preview appears with the duplicates listed below—you can see the name of each, along each version’s path, size, and modification date. (Duplicate Detective uses Quick Look to show previews. This means that for supported file types—image, audio, video, and text files, for example—you see a preview of the file’s contents right in the Duplicate Detective window. For other types of files, you see a preview icon.)

Within the duplicate list you can choose to keep the newest or oldest version from within the selected group (based on modification date; if those are identical, the app uses the creation date). Alternatively, the Auto Select button automatically chooses either the newest or oldest version within each group. (You choose, in the app’s Preferences window, whether Auto Select saves the newest or oldest version.)

With your choices made, click Next. A list of all the selected-to-delete files appears, so you can verify your selections. Once you’ve done so, click Clean, and those duplicates are moved to the Trash. The Trash isn’t emptied, however, so you’re welcome to check it one final time before you finally delete the files within (by manually emptying the Trash).

Bare bones though it is, Duplicate Detective offers a couple of customization options. Within its Preferences window, you can exclude certain folders from the app’s scans. For example, if you’re concerned that you might lose an important image, you can exclude your Pictures folder. (Note that Duplicate Detective won’t scan the contents of a package, such as an installer or your iPhoto Library, unless you manually open the library package and specifically drag one of the enclosed folders to Duplicate Detective for scanning.) You can also tell the utility to skip files that bear a particular file extension—.key, for instance, to lay off any Keynote presentations you’ve created.

But that’s about as fine-grain as Duplicate Detective gets. Other utilities, such as Hyperbolic Software’s $30 Tidy Up, offer scads of customization options and can search not only for exact duplicates, but also similar files—for example, Tidy Up can look for .mp3 and .aac versions of the same audio track. And you may find value in each approach—one app to easily remove exact duplicates, and another when you want to really dig in and find those “this is darned close to that” files. But for quick-and-easy duplicate finding, Duplicate Detective is a nice tool to have on hand.

Want to find out about more cool Mac apps? Check out our Mac Gems session at Macworld/iWorld in San Francisco March 27-29. Want to stay up to date with the latest Gems? You can follow Mac Gems on Twitter or on App.net. You can also subscribe to the Mac Gems RSS feed.

Reader Phil Rogers has more images than he cares for. He writes:

Because digital photos are so easy to save, my wife and I developed the bad habit of downloading, and downloading, and well, downloading. If we needed to show each other something at the store, we’d snap a photo and email it. Then at some point, that orange, or stapler, or whatever, would eventually get downloaded. Net result? Over 50,000 photos in iPhoto, with many duplicates.

How does one even begin to cull the herd? I’ve tried many of the duplicate-finder programs with varied success. But what about just plowing through to get rid of the clunkers?

This is a common problem, particularly now that so many of us carry around cameras (in the form of mobile devices) each day.

Varied success though you might achieve, I’d start with the duplicates. For this kind of thing I like Brattoo Propaganda Software’s $8 Duplicate Annihilator for iPhoto. Unlike some other utilities I’ve tried, it allows you to search by a variety of factors, including SHA1 checksum, creation date, EXIF creation date, first x characters of title, first x characters in filename, width, height, and file size. It also provides you with plenty of results options—what to do with the duplicates that the app finds (trash them, rename them, and so on). If your iPhoto library is anything like mine, eliminating the duplicates will put you way ahead of the game.

Duplicate Photos Detective Show

Detective work

With that done I’d then create a strategy for eliminating the clunkers based on their EXIF (EXchangeable Image Format) data. When you take a picture with a digital camera, metadata (the EXIF data) is embedded in it. This metadata is searchable within iPhoto and other apps and if you can pinpoint those images that are likely to be crummy based on information in the EXIF data, you’ve made a better start.

For instance, if you enter 240 in iPhoto’s Search field, any 240 by 180 thumbnail images will appear. These are surely candidates for the scrap heap. (Note that such a search will also cause 2400 pixel images to appear in the list of results, so be sure you’re tossing an actual thumbnail rather than a larger image that has 240 somewhere in its EXIF data.)

Do you have a less-than-terrific camera in your past? Though it may have captured a few precious memories, perhaps a lot of its images are no longer up to snuff. Find out by searching for its name—CrudCam A200, for example. Weed out the ones you don’t want.

Or consider the situational camera. You say that you snap pictures of items at the store. I’m going to guess that you didn’t do this with a DSLR bur rather with your phone. If this is a habit, maybe you should search for any images taken with an iPhone 4s (or any iPhone model you’ve owned) and remove its worst efforts from the results.

Get smarter

This is all well and good, but sometimes it helps to search for more than one bit of information. For example, pictures shot in really low light with your iPhone 4s. The Search field does no good because you can’t combine queries. But you can with a smart album.

Choose File > New Smart Album and in the resulting sheet configure the first condition to read Camera Model is Apple iPhone 4s. Click the plus button to create another condition and configure it to read ISO is greater than 1250. Make sure that the Match pop-up menu reads All, name your smart album, and then click OK.

Any images that meet these conditions—an iPhone 4s pushing really hard to capture images in low light—will appear in the smart album. Again, some of them may be keepers because they document important events, but they’re not going to be great-looking pictures.

You can use this smart album technique with a wide variety of conditions. For example, if you’ve used iPhoto’s Faces feature to identify the people who appear in your pictures and never want to see that miserable worm JoJo again, just search for any images that contain him and banish them.

The rub is that you can’t delete images from a smart album, so you’ll have to consider your next steps. One option is to select a poor image and choose Show Event from the small menu in the image’s bottom-right corner. This will take you to the event that holds this image. With luck, other images in this event are also not worth keeping. Delete those you don’t want.

Another option is to select all the images you don’t care for within the smart album and then rate them with 1 star (once they’re selected press Command-1 to assign the rating). Repeat this process with other smart albums and images. Once you’ve finished the job, select Photos in the Library column, click on the Search icon in the bottom-left corner, choose Rating, and click on the first star. Any images you’ve assigned a single star rating to will appear. These you can select and delete.

Finally, at the risk of appearing to be a scold, you may wish to be a bit more careful about which images you choose to import in the future. Do so and you won’t have to go through this kind of thing five years from now.

Duplicate Photos Detective Agency

Have a question of your own? Drop a line to mac911@macworld.com.