How can I find duplicate files on my Mac? Duplicate files, especially those with large size, can eat up a lot of storage on a Mac computer. The problem with duplicates is that you don't know when you downloaded multiple copies and over what time frame. That makes them harder to find the duplicates. You can delete them manually, of course, but that would be a labor-intensive task. You can also find and delete them using command line executions on Terminal. Finally, you can search for a good utility that will take care of the problem for you, not just once but on a regular basis.

Before we describe the three methods, keep in mind that finding duplicate files is a tricky thing because of different file names, different versions of the same file, different download times and so many more variables. The first method shown below will make your manual search a little easier and a little more fruitful.

• Part 1. Delete Duplicates Manually
• Part 2. Automatically Locate and Delete Duplicate Files
• Part 3. Find and Remove Duplicates via Command Line

Part 1. How to Find Duplicates on Mac Manually (Photos/Downloads/Mails)

Get ready to dive in for at least a couple of hours if you haven't ever done this on a computer you've been using for maybe 2 or 3 years - or more. However, there are a few tricks to help you get to the most obvious duplicates, as well as the largest of these.

Start with the Photo Library, which you can access from a new Finder window. A lot of users don't realize that if they manually transfer the photos and then also import them to the Photos app, there are now two copies of each image. No wonder your memory looks like it's being eaten up so quickly. It is! If you want, you can delete all the photos in the Photos app. If you've already transferred the files another way, then these are all guaranteed duplicates so it will save a lot of time if you just empty the Photos app's cache of images.

Another way is to search the All My Files category in Finder, and sort by name and size to have all the duplicates grouped together. This usually works unless you haven't specified a naming convention for the photos. In such cases, sorting them by size will help. But make sure you're previewing images for a quick visual check to avoid deleting originals.

This is obviously an error-prone method and will leave a lot of duplicates undetected and still sitting there hogging up disk space, but it should allow you to sort of 'skim the surface' and get all the obvious duplicates out of the way. Just remember to empty the 'Recently Deleted files' after you're done, or else you'll be missing the whole point of the exercise.

Part 2 : How to Automatically Find and Delete Duplicates on Mac with CleanGeeker App

A lot of people prefer using third-party apps to clean up the Mac disk becasue of it takes less time and effort. TunesBro CleanGeeker is one of the best mac cleaning apps you can put trust on. It is the right app you've been looking for ever since your computer slowed down and started acting like a senior citizen. Using complex algorithms, this software will identify duplicates, junk files, residual files left by apps and a whole lot more. In addition, it can securely shred digital files and even extract RAR files.

When it comes to duplicate files, CleanGeeker is second to none. It clearly labels your duplicates so you can spot and keep the original while automatically removing everything else with just one click. It even categorizes them so you can visually see where duplicates are getting piled up.

Step 1Install TunesBro CleanGeeker on Mac

Download the application and install it on your Mac computer. It supports all versions of Mac OS X right up to macOS Mojave (10.14).

Step 2Scan Duplicates on Mac

Run the program and go to the 'Duplicate Clean' tab on the left side. In the middle you'll see the full list of files for which duplicates were found, and on the right you'll see the original along with the duplicates. The originals will be unchecked, while the duplicates will be checked by default.

Step 3Choose Duplicate Files and Delete Them from Mac

Select or deselect the files you want to delete or keep, respectively, and then click on 'Delete' on the bottom right. Then all selected items will be completed removed from the computer.

Part 3. How to Find and Remove Duplicates via Command Line (Terminal)

If you're feeling less pedantic and more adventurous, you can try a simple Terminal command to find duplicates. In truth, it's merely a bit of a short cut because you'll have to do the deletion on your own. But it helps by finding duplicates and listing them in a text document for you to review.

Step 1. First, open an instance of Terminal from Applications >> Utilities.

Step 2. Then use the cd command to navigate to a particular folder. For example, if you want to go to the downloads folder, type in the following command and hit Enter: cd ~/Downloads

Step 3.Once you're inside a folder, here's the next command you need to use in Terminal:
find . -size 20 \! -type d -exec cksum {} \; | sort | tee /tmp/f.tmp | cut -f 1,2 -d ‘ ‘ | uniq -d | grep -hif – /tmp/f.tmp > duplicates.txt

Don't worry if you don't understand what the command says. What it does is to create a list called duplicates.txt which you can review prior to going in and deleting the files themselves. This is also a time-consuming method, but with a small shortcut to help you identify where the most number of duplicates are.

Summary

According to the methods suggested about, CleanGeeker finds every single duplicate in your hard drive so you don't have to do anything folder by folder. You'll be spending a few minutes at the most for this entire process, and you can do it periodically to make sure duplicate files never clog up your memory ever again. You'll be hard-pressed to find another software application that removes unnecessary files so effectively.