1. Launch Disk Utility. Either head to Applications Utilities, or tap Command + Space and start typing.
2. Step 7: From the Volume Format menu, choose Mac OS Extended. Step 8: Enter a name for the external hard drive in the Name field. Step 9: Click the Erase button. How to Reformat in Windows. Step 1: Plug your external hard drive into your computer. Step 2: If you have already written any data to the drive, back it up before proceeding to the next.
3. Part 2: Format External Hard Drive for Mac with Disk Utility. Formatting an external hard drive would erase everything on it. Hence, you must backup your important files before reformatting the drive if you want to save them. The easiest way is to drag it from one drive to another. All is set, then you can go ahead to format the drive on your Mac.

Most external hard drives are designed to work for Windows computers. So if you’re trying to connect an external hard drive to a Mac, you might have to format the drive before you can use it. Here’s how to do that:

How to Format a Hard Drive for Mac

Note: If you already used your external hard drive on a PC, be sure to back up any files on it. Formatting your drive will wipe out all the data in it.

This article explains about file systems and provides instruction to format a drive on Windows and Mac. Newer Seagate and LaCie branded external drives come preformatted exFAT, some older drives are formatted for PCs, some for Macs, and some of them have special utilities allowing them to work between both without formatting.

1. Connect an external hard drive to your Mac. Some external hard drives need to be plugged into an outlet to work.
2. Go to Spotlight Search, type in Disk Utility, and click the first option. This will open the Disk Utility app, where you will find all the internal and external drives that are connected to your Mac.
3. Then click View in the top-left corner of the window and select Show All Devices.
4. Click the external hard drive you want to format. You can find this on the left-hand side of the screen under External Hard Drives. For the best result, select the disk (the highest option in the external tree).
5. On the top menu, click Erase. This will open a small pop-up window with a warning that erasing the drive will delete all data stored on it and that it can’t be undone.
6. Choose a name, format, and scheme for your drive. You can choose whatever name you want, and you should choose GUID Partition Map for the Scheme in most cases. However, you can choose between the following formats:
   • Mac OS Extended (Journaled) is the best option for most Mac users since it is compatible with all Macs.
   • APFS (Apple File System) is only for newer Macs running macOS 10.13 or later.
   • exFAT is compatible with both PC and Mac.
   • MS-DOS (FAT) is also compatible with Mac and PC, but you can only transfer files smaller than 4GB.
7. When you’re done with providing the setup details, click Erase. This will immediately wipe the entire drive.

If you get an error message that states, “Erase process has failed. Click done tocontinue,” don’t freak out about it. This is an issue caused by Time Machine running on your externaldrive.

You will need to turn off Time Machine. You can do this by opening System Preferences and unchecking the boxnext to “Back Up Automatically”.Then click Options beside “ShowTime Machine in menu bar.” This will open another window. Click Cancel and it will turn off the Time Machine.

After you turn off the Time Machine, redo steps 4 to 6.

How to Partition anExternal Hard Drive on Mac

If you have formattedyour drive, you can then partition the drive, which will splitthe drive into two formats. This is perfect for anyone who uses Macs and PCsand wants to transfer files between the different operating systems with anexternal drive. Here’s how to do that:

1. Open Disk Utility and select the drive that you want to partition. It is best to click View > Show All Devices so you can selectthe disk rather than a container.
2. In the top menu, select Partition.
3. Then click the plus sign at the bottom of the pie chart. Every time you click this plus sign, a new partition will becreated.
4. Choose a name, format and size for each partition. You can also change the size of each of the partitions bydragging the white dots at the edge of the circle.
5. Finally click Apply.

Why Partition a Hard Drive?

Partitioning an external hard drive allows youto have separate drives for Mac, PC, and any other operating system. Now youdon’t have to go out and buy hard drives for every computer you use.

A partition also gives you a dedicated space foryour Time Machine back-up files or a bootable backup of your operating system.It also helps protect your data if your drive gets infected with malware, as itwould be contained within one of the partitions.

Now that you know how to format an external drive for Mac, check out our blog on the difference between an HDD and an SDD.

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Oct 13, 2020 • Filed to: Answer Hard Drive Problems • Proven solutions

External hard drives are the storage devices used to store and retrieve digital information, personal and official data like files, documents, and other stuff. These are attached to systems through FireWire or USB connection or wirelessly to transfer data from the internal drive to hard disk drives. If you are looking for a new operating system or selling your old computers or laptops, then you need to set up an external hard drive for backups by erasing and formatting the existing data in the storage devices.

• Part 1:　How to Format an External Hard Drive on Windows
• Part 2: How to Format an External Drive on Mac

Part 1:　How to Format an External Hard Drive on Windows

The Windows users who are going to format the external hard drive for the first time, they will get complete information and stepwise procedure of formatting drives.

Stepwise Procedure to Format Storage Device on Windows:

1. Before formatting an external hard drive on Windows, back up all the informational data like files, music, and official data into a safe place.
2. To format an external hard drive, plug in the device into a system or a wall outlet.
3. After plugging in the hard drive into the system, you will get the option to open Windows Explorer and by clicking on the computer section in the sidebar, you will see your hard drive get attached to your system.
4. When you will do right click on the hard drive icon, you will get the option to choose 'Format'?.
5. After that, you can opt for any file system that you want to use for the operating systems.
6. Mention your hard drive with a name under Volume Label and check out the Quick Format box.
7. To initiate the formatting process, click on the start button and within a few seconds, you will get a notification when the process gets completed.
8. Open the hard drive in Windows Explorer and start dragging documents and files into it.

Follow the stepwise procedure to format an external hard drive and make sure it will not show similar free space as it displays on the box as the systems determine the space differently as it is marked on the box.

Video Tutorial on How to Format External Hard Drive

Format External Drive For Mac Mojave

Part 2: How to Format an External Drive on Mac

Mac users can select any file system that supports their operating system. To format an external drive on Mac, you can follow the stepwise procedure as discussed below:

Stepwise Procedure to Format Storage Device on Mac:

1. Before starting the storage device formatting process, you need to backup all informational data in a separate folder for future use.
2. Plugin the storage drive into Mac.
3. The drive when get connected to the system, you can see the storage device icon on the screen.
4. Now open the finder and check out the applications/utilities. After that, operate double click on the disk utility.
5. To format the external hard drive, opt your storage device in the left-hand sidebar and click on the erase tab.
6. After that, you will see a format menu where you can select the file system that is compatible with your operating system.
7. Describe or provide a specific name to your drive and click on the erase button. Within a short period, your storage device will get formatted.
8. When you are done with the formatting process, click on the hard drive in the finder and initiate the dragging process or you can also set up as a backup storage device with Time Machine.

By following the stepwise procedure mentioned above, you can easily format the storage device on Mac.

What is External Hard Drive Formatting Process?

Format External Drive For Mac And Windows 10

Formatting external hard drives is a process of deleting or erasing the memory chunks to avail the space for new data. Formatting can be performed at two stages: low level and high-level process. Formatting may take a few hours to wipe out the existing data, but the process can be hassle-free if you get to know about stepwise instructions on how to format an external hard drive.

Low-level formatting is the first process of wiping out data and existing files in the hard disk devices and at the high level, a new file system is generated. Technically, it is the process of writing a new directory structure that allows the documents and files to be overwritten and create space for the new data.

Before formatting external hard drives, backup all important data that you are going to format. Most external hard devices come with backup software that will make the process much easier to do. If you have documents, music, photos saved elsewhere on the computer then make sure you have copied all stuff before formatting. Remember once all the data get formatted, it will not be recovered at any cost.

File System Explained:

Before proceeding to format the external hard drive, you need to know about file systems that are particularly associated with the operating systems. File systems are the key parts of translation from the physical data recording on a hard drive to the files that are read by operating systems only.

Various operating systems like Mac, Windows, Linux, and OS X have different file systems to organize and store digital information. The most popular file systems are as discussed below:

Format External Drive For Mac And Windows

• NTFS (New Technology File System): NTFS is developed by Microsoft, started with Windows NT 3.0. It is also known as Window's default file system. Microsoft has launched five versions of NTFS: v1.0 released with Windows NT 3.1, v1.2 with Windows 3.51, v3.0 with Windows 2000, v3.1, and v5.0 with Windows XP. The latest version includes many features like disk usage quotas, link tracking distribution, reparse points, file-level encryption, and sparse file support. Windows can write and read to NTFS formatted hard drives while OS X and Linux can read-only but can't write unless it is supported by third party devices like NTFS-3G. It has a maximum of 16 TB file size and 256 TB volume size.
• FAT 32 (File Allocated Table): It was designed in the year 1977 for floppy disks and three major file systems variants are: FAT12, FAT16, and FAT 32. The older version of FAT was quite simple and robust. FAT32 has come up with the increased number of bits which is used to address clusters. It also helps to reduce each cluster size due to which it will have great storage capacity and effectively support the large disks up to 2 TB. It can be written and read by Linux, OS X, and Windows. FAT32 offers a maximum of 4GB file size and 2 TB volume size.
• ExFAT (Extended File Allocated Table): It is quite similar to FAT32 and is less commonly used. ExFAT can store up to 4GB files which make it perfect for flash drives. ExFat formatted drives can be read and written by OS X and Windows.
• HFS Plus (Hierarchical File System): It is developed by Apple Inc. It serves as the primary file system of OS X and also known as Mac OS Extended. For those who are operating Windows on Mac with Boot Camp, they can read HFS plus hard drives but can't write to them. However, third-party tools like Paragon HFS+ assist the users to write and read to HFS+ drives. HFS plus offers 8 EiB maximum file size and volume size.

These are the popular file systems for Windows, Mac, and Linux operating systems. For those who are running Windows computers, they can format hard drive as NTFS, and for the Mac users; ExFAT will be the best and reliable option. Before formatting external hard drives, make sure you have created a backup for the all-important digital data. Nowadays, it is also possible to convert hard drive without losing any>Recover Your Drive

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