Learn how to format USB drive external on Mac? On this page, you can also learn how to make your USB always readable and writable on Mac.
Whether you're transferring files, upgrading your storage, or troubleshooting issues, formatting a USB or external drive is a common task for any Mac user. You might find that your drive is not working as expected or you want to change its format to be compatible with macOS. Formatting essentially prepares your drive for use by creating a file system.
Formatting is often necessary when:
◆ Your drive is incompatible with your Mac and needs to be reformatted to a compatible file system.
◆ You need to erase everything on the drive for security or performance reasons.
◆ Your drive is experiencing errors that cannot be fixed by simple repairs.
By formatting the drive correctly, you ensure that your data is safely stored and your external device works seamlessly with your Mac.
When it comes to formatting drives on a Mac, the file system you choose is crucial. The file system determines how data is stored and accessed on your drive. Here's a breakdown of the most common file systems used on macOS.
>>Ideal for SSDs and macOS 10.13 (High Sierra) and later.
>> Offers strong encryption, space sharing, and high performance.
>> Not compatible with older macOS versions or Windows PCs.
>> Used on older Macs and external drives.
>> More compatible with legacy macOS versions but lacks modern features like encryption available in APFS.
>> Best for compatibility between Mac and Windows.
>> Supports large file sizes and works well with flash drives and external hard drives.
>> An older format still used for compatibility with a wide variety of devices.
>> Limited to 4GB file sizes, which may not be ideal for large files.
If you’re using macOS 10.13 or later and primarily on a Mac, APFS is your best choice. For drives used across both Mac and Windows, exFAT is ideal. HFS+ is suitable for legacy systems or older macOS versions.
Formatting a USB or external drive on macOS ensures compatibility, fixes errors, and prepares the drive for proper use. Below are two reliable methods you can follow.
Disk Utility is the built-in macOS tool for managing your drives. It’s simple, straightforward, and can help you format your USB or external drive in just a few steps.
Step 1. You can find Disk Utility by searching for it in Spotlight or by navigating to Applications > Utilities > Disk Utility.
Step 2. In the left sidebar, locate and select the USB or external drive you want to format.
Step 3. Click the Erase button at the top of the window.
Step 4. A dialog box will pop up, allowing you to choose the drive's name and format.
Step 5. Select the appropriate format (APFS, exFAT, HFS+).
Step 6. Choose GUID Partition Map if the drive is larger than 2TB or needs to be bootable.
Step 7. Click Erase to begin the formatting process. Wait for it to complete.
Step 8. Once finished, your drive is ready for use.
If you prefer to use the command line or need more control over the formatting process, Terminal provides a powerful alternative.
Terminal is a command-line interface on macOS that allows you to execute advanced system commands. It’s a more technical option but provides flexibility for advanced users.
Step 1. Find Terminal in Applications > Utilities > Terminal.
Step 2. Type diskutil list to see all connected drives. Identify the drive you want to format.
Step 3. Use the following command to format the drive:
sudo diskutil eraseDisk exFAT MyDrive /dev/diskX
✱ Replace MyDrive with your desired drive name and /dev/diskX with the appropriate disk identifier from the previous step.
Step 4. Type your administrator password when prompted, and wait for the process to complete.
PartitionAssistant NTFS for Mac is a dedicated NTFS driver that enables full read and write access to NTFS-formatted drives on macOS.
By default, macOS can only read NTFS drives, meaning you can open files but cannot edit, copy, delete, or save new data.
This tool removes that limitation and gives your drive full functionality—just like a native Mac disk.
Once installed, your USB or external drive becomes fully writable on Mac, allowing you to:
✔️ Copy files to NTFS drives
✔️ Edit and save documents directly
✔️ Delete or rename files
✔️ Move data between Mac and external drive
✔️ Drag and drop files in Finder normally
All these operations work seamlessly without reformatting your drive.
Step 1. Download the USB NTFS for Mac tool and follow the instructions to install it on your Mac. Then open PartitionAssistant NTFS for Mac. Connect your drive to the Mac. The software will find it and show it on the screen.
Step 2. Select the USB you want to operate. If the state is "Read Only", please click "Enable Writable".
When the state change to "Read & Write", you can click "Open", then copy, delete, and rename files on your Mac.
Step 3. After all operations are complete, please click "Eject" to disconnect the USB from your Mac.
Formatting a USB or external drive on Mac is essential for ensuring compatibility, resolving errors, and optimizing performance. By choosing the right file system and using tools like Disk Utility or Terminal, you can easily prepare your drive for seamless use. If you need full write access to NTFS drives without formatting, Partition Assistant NTFS for Mac offers a simple and effective solution.