Recommend me a best duplicate file finder for Mac M2?

Ramburt wrote:

I was organizing the files on my MacBook M2 recently and found that the photos, documents, and materials had been piled up for several years. I guess there are a lot of duplicates. It's too troublesome to manually compare them one by one. I want to find a duplicate file finder tool that can automatically scan and identify duplicate files. It's better to preview them to avoid accidentally deleting important things.

My experience is that such apps create a lot of false positives. So, even if you use one, you still have to go through everything to make sure that it didn't flag something as a duplicate that really isn't.

You can go with the shasum, is a command-line duplicate file finder utility on Unix-based systems (like macOS.) It can be used to compute SHA checksums for files or strings. By default, it uses SHA-1, but it also supports stronger algorithms like SHA-256 or SHA-512 with the -a option.

shasum is ideal for finding duplicate files because it compares files by their actual content, not by name, size, or metadata. Even a 1-byte difference in file content will produce a completely different hash. Most importantly, it is scriptable and works well as duplicate file finder for mac in bulk via tools like find, sort, and awk.

Example:

shasum file1.mp3
shasum file2.mp3

If the output hash is the same, the files are likely identical, even if the names differ. This is a simple way to find and remove duplicate files on Mac.

There are at least three types of duplicates you need to deal with ...

1. Files with the same name & content but located in different folders.
2. Files with the same name, located in different folders, but having different content (often versions of a document)
3. Files with different names but having identical content (often photos)

Disk Drill is pretty impressive in this regard. Duplicate File Finder is also a reasonable choice for what you want to do.

I advise staying away from terminal commands especially if you are not experienced using Terminal or if you don't have experience with the particular commands. Extreme caution is advised when using Terminal ... mistype a command or key in a wrong command or option and you could hose all or part of your system.

The Terminal app is a good free duplicate file finder for Mac. It is one of the best choices if you are comfortable with text commands.

Now, open the Terminal app and go to the destination folder where holds duplicate files.

Run the following command to find duplicate files on Mac by comparing the MD5 hash:

find . -type f -exec md5 {} + | sort | awk '{
    if ($NF in seen) {
        print seen[$NF] "\n" $0 "\n"
    } else {
        seen[$NF]=$0
    }
}'

What it does:

• find . -type f searches all files in the current directory and subdirectories.
• md5 computes each file's hash.
• awk compares the hashes and prints duplicates.

I've been through the same process on my MacBook M2 recently — years of documents and photos piling up, and manually comparing duplicates is nearly impossible. The good news is that most modern duplicate file finders now support Apple Silicon and macOS Sonoma natively.

Here's what I'd suggest:

1. Look for Universal Binary apps

Many older tools haven't been updated for M1/M2 architecture, which can cause slow scans. Make sure the app specifically says it supports Apple Silicon.

2. Preview before deletion

This is key — some tools flag similar but not identical files (e.g., resized images, edited docs). Always use one that lets you preview content side-by-side before removal.

3. Try a lightweight, ad-free option

Some of the "free" apps are filled with ads or limit basic features. A paid but well-optimized tool often saves hours of frustration.

[Edited by Moderator]

Haudeda wrote:

I recommend trying out Gemini 2 or Easy Duplicate Finder as they are both popular and reliable options for finding and removing duplicate files on Mac M2, including support for macOS Sonoma.

Yikes! Gemini 2 is developed by MacPaw, the infamous makers of CleanMyMac, also known as BrickMyMac. With a simple search in these forums by using the Search option on the top of the screen, you will also see the posts from users who have installed Gemini 2 and now cannot remove it from their Mac. While that is a common recommendation seen with AI responses due to the heavy marketing by MacPaw, it is not a factually sound solution to make recommendations from what is found simply through a AI request.

etresoft wrote:

The operating system automatically prevents most duplicate files. You would really have to go out of your way, using an external drive, in order to create a duplicate file in the first place.

No I've found it quite easy - running Duplicate File Finder on my system revealed the duplication of some folders with their files. This app shows useful lines of attack for such cases.

mechanic1357 wrote:

No I've found it quite easy - running Duplicate File Finder on my system revealed the duplication of some folders with their files. This app shows useful lines of attack for such cases.

Duplicate files don't actually exist. You are actually talking about the same file being referenced by two different file pointers. These duplicates don't take up any extra space.

It is possible to create actual duplicate files, but it isn't easy. You would have to do it on purpose.

So please tell us what these deleted files are in ~/Trash? They don't look like links but like real files with listed sizes. Bash shows some detail, and the shell tells us that they are real files, not links.

mechanic1357 wrote:

So please tell us what these deleted files are in ~/Trash? They don't look like links but like real files with listed sizes. Bash shows some detail, and the shell tells us that they are real files, not links.

I have no idea what files are in your Trash. I don't recommend looking directly in "~/.Trash". The "Trash" is a Finder artifact. The fact that it is currently implemented as a hidden directory in your home directory (in some cases) doesn't mean that you should ever make use of that. This has nothing to do with your question, but since you mentioned ~/.Trash, I thought I should caution you about it.

Links are older file system artifacts. There are a few different kinds of links. They all require some special procedure to create. If you copy or duplicate a file on a modern system, it will create a clone. A clone will be identical to the original in every way. It will be a file, not a link.

The file system has poor support for identifying when file is a clone. So any app that is reporting a "duplicate file" probably hasn't been able to identify the file as a clone. Deleting that clone will recover zero bytes of data.

Furthermore, if you make any changes to a clone or a file that has been cloned, then you'll wind up with a partial clone. Any duplicate file finder app will report that the file as not a duplicate, when it could be 99.9999% duplicated data.

You can try Cisdem Duplicate Finder. I’ve tested several duplicate file finders, and this one has the best preview feature. It lets me compare duplicates side by side, which is especially helpful since I have lots of similar photos. Being able to view a group of duplicates in one window makes it easy to decide which version to keep.

The operating system automatically prevents most duplicate files. You would really have to go out of your way, using an external drive, in order to create a duplicate file in the first place.

You can follow this simple tricks to find duplicate files on Mac. It works on intel and apple silicon mac.

On.

macOS.

There.

Are.

No.

Duplicate.

Files.

Q.E.D.

I recommend trying out Gemini 2 or Easy Duplicate Finder as they are both popular and reliable options for finding and removing duplicate files on Mac M2, including support for macOS Sonoma.