How to Find Duplicate Files on Mac: Complete Guide to Free Up Storage

  

Published By Aunraag Singh

Approved By Nimisha Ramesh

Published On November 10th, 2026

Reading Time 9 Minutes Reading

You can find duplicate files on Mac by using Finder Smart Folder to compare file size and name, running Terminal commands to match file content, checking duplicate albums in the Photos app, or using a duplicate file finder tool. These tools can scan folders and find duplicate files automatically. If you have large folders, a duplicate finder tool is the fastest option for you.

If your storage is almost full, duplicate files may be one of the reasons. Sometimes, you download the same file from different browsers or websites. You may also save the same PDF in multiple folders and forget to delete extra copies.

In this guide, you will learn how to find duplicate files on Mac in four different ways, which method to use for each situation, and how to delete duplicate files without losing important files.

Why Do Duplicate Files Appear on a Mac?

Before scanning for duplicate files on Mac, you need to understand how duplicate files are created on your device. When you know the reasons, it becomes easier to avoid creating duplicate files and organize them in the future.

• Multiple downloads: When you click multiple times on a download link, the same file may create extra copies and get saved on your Mac. Numbers may be added at the end of the file name, such as invoice (1).pdf.
• Photos and media imports: When you sync photos or media from your phone, external drives, or cloud libraries, files may be saved in different folders on your Mac.
• Project backups: When you copy folders to save your work, older copies may remain in your Desktop and Documents folders.
• App caches and attachments: Mail or messaging apps may create extra copies of files that you have already saved in other folders on your Mac.

Comparison of 4 Methods to Find Duplicate Files on Mac

Different methods work for different situations. The right method depends on how many files you have and how much duplicate data you want to remove from your Mac.

Method 1: Find Duplicate Files on Mac Using Finder Smart Folders

macOS does not have a direct button like “Find Duplicate Files,” but you can manually search for duplicate files on Mac using Finder Smart Folders. This method is useful for identifying files with similar names and sizes.

1. Open Finder from your Dock.
2. Click on File in the top menu and select New Smart Folder.
3. Check that This Mac is selected at the top of the window.
4. Click the + (plus) button in the upper-right corner.
5. Select Kind from the first dropdown menu and choose categories such as images, documents, or PDFs.
6. Switch to List View and sort files by name and size to find similar files on Mac.
7. Select the extra copies you want to remove, right-click, and choose Move to Trash.

Pro Tip: Before deleting any file using Finder, check the Date Modified column. This helps you keep the latest version of the file.

Limitation: Finder helps identify duplicate files on Mac based on file names and sizes. If you have duplicate files with different names, they may be missed. On the other hand, two different files with the same name may look like duplicates even when their contents are different.

Method 2: Identify Duplicate Files on Mac in the Photos App

If your Mac contains a large collection of photos and videos, the Apple Photos app has a built-in feature to help you detect duplicate files in your photo library.

1. Open the Apple Photos app.
2. In the left sidebar, click Duplicates under the Utilities section.
3. Review duplicate photos and videos grouped side by side by macOS.
4. Click Merge next to a pair or select multiple pairs and choose Merge [Number] Items.

Apple Photos keeps the highest-resolution images along with their captions, keywords, and edits. The extra copies are moved to the Recently Deleted album.

Limitation: This feature works only within the Photos library. It does not work with other folders, such as Documents, Videos, Downloads, or Archives.

Method 3: Use Terminal to Find Duplicate Files on Mac

If you want to find duplicate files on Mac without installing extra software, you can use Terminal. It compares digital fingerprints (checksums) to detect duplicate files.

Even if two files have completely different names, Terminal can identify them as duplicates if their content is exactly the same.

1. Open Finder, go to Applications > Utilities, and double-click Terminal.
2. To scan your Documents folder, use the command below. You can replace ~/Documents with ~/Downloads or ~/Desktop to scan another folder.

find ~/Documents -type f -exec shasum -a 256 {} + | sort | awk '$1==prev{if(!shown)print line; print; shown=1; next} {prev=$1; line=$0; shown=0}'

3. Press Return and wait for the scan to complete.
4. Review the file paths shown in the Terminal window. Files with the same SHA-256 hash have matching content.
5. Copy the file paths you want to remove and delete the extra copies safely through Finder.

Safety Note: This command only reads files and displays matching results on the screen. It does not automatically delete any data.

Limitation: Terminal displays results as plain text and does not provide file previews. Scanning large folders can take time. There is also a risk of deleting the wrong files if you use incorrect commands.

Method 4: Scan Mac for Duplicate Files Automatically with FreeViewer

When you have thousands of files stored across internal drives, external SSDs, or nested folders, manual methods can become slow and difficult.

In this situation, you can use FreeViewer Mac Duplicate File Finder for faster and more accurate scanning.

Key Advantages of Software

• Exact Content Matching: This tool does not depend on file names. It compares the actual file content using file hashing.
• Supports Different File Types: It can scan different file types, including documents, audio files, videos, archives, and photos on your Mac and external drives.
• Safe Auto-Selection: It automatically finds duplicate files on Mac and protects one original copy in each group.
• Preview Before Removal: You can check the files before deleting them.

Steps to Find and Remove Duplicate Files on Mac

1. Download and install the FreeViewer Mac Duplicate Finder tool.

2. Launch the software and click Add Folder or select the drives you want to scan.

3. Choose scan filters such as file types and minimum file size. Click the Continue button.

4. Review the list of duplicate file groups after the scan is complete.

5. You can keep one original copy safe by choosing the Recursive option.

6. Click the Delete button to remove extra copies of duplicate files and free up disk space.

For more information, visit the guide page.

Why Use a Duplicate File Finder Tool?

• It does not detect duplicate files based only on file names. It compares file content.
• The tool allows you to preview files before deleting them.
• It scans large folders faster than manual methods.
• It works with external drives as well as your Mac.
• It allows you to move duplicate files to another location instead of deleting them permanently.

Safety Checklist Before Deleting Duplicate Files

If you delete the wrong files, some applications may stop working, and your important data may be lost. That is why you should follow these instructions before deleting duplicate files on Mac.

• Never Scan System Folders: Avoid deleting files from folders such as /System, /Library, or /Applications because macOS needs these files to work properly.
• Empty the Trash Afterwards: Moving duplicate files to Trash does not immediately free up storage space. You must empty the Trash to free up space.
• Back Up First: Create a quick Time Machine backup before performing a large cleanup on your MacBook.
• Check External Drives Separately: If you want to remove duplicate files from external USB drives or SD cards, keep them connected while scanning.

Easy Habits to Avoid Duplicate Files in the Future

If you want to avoid keeping duplicate files on your Mac, follow these simple habits:

• Clean your Downloads folder every month.
• Do not save the same file in multiple folders.
• Use clear file names instead of words like “copy” or “final 2”.
• Check existing photos before importing new photos.
• Run a duplicate file scan every few months.

Conclusion

Now you know which methods you can use to find and delete duplicate files on Mac. Finder and Terminal help you find duplicate files manually, while the Apple Photos app helps you manage duplicate photos.

If you have too many duplicate files on your MacBook, finding and deleting them manually can become difficult. You can use FreeViewer software to find and remove duplicate files on Mac.

Before deleting any files, check them carefully and create a backup of your important data. You should run duplicate scans every few months to prevent your MacBook from filling up with unwanted files.

Common Questions About Duplicate Files on Mac

Question: Does macOS have a built-in duplicate file finder?

Answer: No, macOS does not have a single tool to find all duplicate files on Mac. The Photos app can find duplicate images, while Finder and Terminal can help you identify similar or identical files using different methods.

Question: How can I remove duplicate files on my Mac for free?

Answer: You can use Finder to find extra copies by sorting files by name and size. You can also use the Photos app to find and merge duplicate images and videos.

Question: Is it safe to delete duplicate files on a Mac?

Answer: Yes, it is generally safe to delete duplicate personal files, such as documents and downloads, after checking them carefully. Make sure you do not delete important system files or application folders.

Question: Why does my Mac still say storage is full after deleting duplicates?

Answer: When you delete duplicate files, they may move to the Trash instead of being permanently removed. You should empty the Trash to free up storage space.

Question: What is the best free duplicate file remover for Mac?

Answer: FreeViewer Duplicate File Finder is a suitable tool for finding and removing duplicate files from Mac. Check its available features and free version limitations before using it.