Buying an external hard drive or SSD for your Mac is not all that different from buying one for your Windows PC. Most laptops with either operating system now come with at least one oval-shaped USB-C port, and it's the one you'll want to use for connecting your external drive. The main difference is that many drives made specifically for Macs use the upgraded Thunderbolt data transfer protocol, which promises super-fast data transfers for photographers and video editors who need to store mountains of footage and access it very quickly. As a result, they are typically external SSDs, or even multidrive RAID arrays, which means they also tend to be expensive.
So what's a Mac user to do who just wants to back up his or her files using Time Machine, or stash a large video collection? Spoiler: A Thunderbolt drive isn't your only option; far from it. In fact, in many cases it makes sense to choose an inexpensive non-Thunderbolt drive that isn't targeted toward Mac use. Read on as we solve this and all of your other Mac external-storage quandaries.
The only drive that is listed is the drive for the Internet Recovery OS install. Booted from Thumb Drive (Create a bootable installer for macOS - Apple Support) using the Apple USB C AV Multipart Adapter, but I still had no internal disk showing up to install the OS on in the installation menu. Disk utility also still shows no internal hard drive.
File-System Considerations
In the Disk Utility app on your Mac, choose View Show All Devices, then select the container you want to erase in the sidebar. If Disk Utility isn’t open, click the Launchpad icon in the Dock, type Disk Utility in the Search field, then click the Disk Utility icon. Click the Erase button in the toolbar. Backup your Mac with a portable or desktop hard drive. Safekeep all of your music, photographs, movies and more. Buy online with fast, free shipping.
Before we get to Thunderbolt, we need to address a basic building block of hard drives that has always affected compatibility, and probably always will: the file system.
An external drive's file system is the most important factor that determines whether or not it's readable by Macs, PCs, or both. Starting with macOS 'High Sierra,' Cupertino ditched its venerable Mac OS Extended file system, commonly abbreviated as HFS+, and switched to an entirely new file system. It's simply called the Apple File System (APFS), and it's the first format to be used across both Macs and iOS devices.
External Hard Drive For Macbook
There are many benefits to switching from HFS+ to APFS, including better security thanks to native encryption, but the most important thing to note for external-drive shoppers is backward-compatibility. Any drive formatted with HFS+ will work just fine with a Mac that's running High Sierra or later.
Neither Apple File System nor HFS+ works with Windows, however. If you plan to use your external drive with computers that run both operating systems, you should consider formatting your drive with the exFAT file system. You won't get the security and efficiency of APFS, but you will get the convenience of being able to transfer files back and forth between Windows and macOS simply by plugging in and unplugging your drive.
Of course, you can easily wipe and reformat most external drives, so you're not limited to buying only those intended for use with Macs. If you really fancy a consumer-oriented drive formatted for Windows (which will usually come pre-formatted in the NTFS format), you can use the Disk Utility in macOS to reformat it after you bring it home from the store. Some highly specialized external drives might not work with Macs even if they're formatted correctly, but consumers looking for extra space simply to store backups or large video collections aren't likely to encounter them.
External Drives: SSDs vs. Spinning Platters
Once you've settled on a file system, you then have to determine which storage medium you want: solid-state or spinning disk. Each has its advantages and disadvantages, and—unlike the file system—the type you buy is the type you're stuck with for the life of the drive.
A solid-state drive (SSD) offers quick access to your data because it stores your bits in a type of flash memory rather than on spinning platters. SSDs are often smaller and lighter than spinning external drives, as well, which is also thanks to the lack of moving parts. Their small size means they can often fit into a jacket or pants pocket, which makes them a better choice if you're looking for a portable external drive that you'll be carrying with you frequently. (See our overall picks for favorite external SSDs.)
One major downside, however, is that they're more expensive. You could pay more than 20 cents per gigabyte for an SSD, while spinning drives can be had for less than 10 cents per gigabyte—and often much less. External SSDs also have lower capacity limits, with most drives topping out at 2TB. Compare that with external spinning drives, which are easy to find even in capacities in excess of 8TB for desktop-style drives, or up to 5TB for portable ones.
For professional videographers who edit lots of 4K footage and gamers or movie buffs who have large libraries of multi-gigabyte titles, an external RAID array made up of multiple platter-based drives is worth considering, since it combines the near-speed of an SSD with the gargantuan possible capacities of spinning drives. An array contains two or more drives that all work together to increase throughput, or guard your precious files against corruption via drive redundancy if one of the drives fail. (Or both; it depends on how the array is set up.) The result is that you can get SSD-like speeds, with throughput of more than 400MBps, and capacities that top out close to 50TB. You'll pay handsomely, of course—some Mac-specific arrays cost thousands of dollars.
On the other hand, if you're looking to buy an external drive mainly to back up your files (which you should definitely do), and it will rarely leave your home office, an inexpensive spinning drive will work just fine. These come in both portable and 'desktop' versions.
The portables are obviously smaller, and are based on the kinds of 2.5-inch platter drives used in laptops. Desktop-style external hard drives are larger, are based on the beefier and more capacious 3.5-inch drives used in full-size desktop PCs, and require their own AC power source. Portable drives don't have a power plug; they get the juice they need to run through their data interface.
Does Thunderbolt Matter, or Will USB-C Do?
So, to recap: Faster, smaller (both physically and in terms of gigabytes) solid-state drives come at a premium, while spinning drives offer a much better value while sacrificing speed. But what happens when you throw yet another variable into the mix: the connection between your drive and your Mac? As you might have guessed, the answer is more trade-offs.
Every current Mac comes with oval-shaped USB Type-C ports that support Thunderbolt speeds. MacBook Pro models released in 2021 come with the latest Thunderbolt 4 interface, while other recent Macs use the older Thunderbolt 3. Both have the same maximum 40GBps maximum throughput, many times the speed of regular USB-C ports.
Unfortunately, you won't find all that many Thunderbolt 3-compatible drives on the market, and even fewer that support Thunderbolt 4. There are even some Mac-specific drives still sold with USB 3.0 connectors. Moreover, the Thunderbolt drives you can buy are constrained by the maximum throughput of the drive itself, rather than the Thunderbolt interface. Until recently, most external SSDs topped out at around 600MBps, for instance, due to the traditional bus types used by the drives inside the chassis. That's more than fast enough for backups and occasionally transferring multi-gigabyte files, but many times lower than Thunderbolt's maximum throughput.
However, that speed ceiling is rising. While older external SSDs have been limited by the internal electronics (generally a drive and controller using the older Serial ATA bus inside the drive), late-model drives use different internal components, based on PCI Express drives using the NVMe protocol. These kinds of components in newer drives help Thunderbolt reach more of its speed potential. Drives with rated peak reads and writes in the 1,000MBps to 3,500MBps range indicate one of these newer-tech drives. (Again, see our roundup of the best external SSDs for more discussion of this.)
You can insist on Thunderbolt support if you know you need all the speed you can get, but a USB-C drive will be a better pick if you're more price-sensitive, or need to also use the drive with a PC. With USB-only drives, some manufacturers include a USB Type-C cable for people who own a USB Type-C-only Mac, and you can always pick up a converter for a few dollars online if the drive you're eyeing doesn't offer one. And don't forget that the 27-inch iMac and Mac Pro still come with USB 3.0 ports, so they won't require adapters.
Other External-Drive Considerations
Drives intended for PCs sometimes come bundled with software that will automatically back up your files to the drive when it's connected, but such software isn't as much of a consideration for Mac users, who already have an excellent built-in backup option in the form of Time Machine. (See our guide to using Time Machine for backups.)
The first time you plug in an external drive, Time Machine will ask if you want to use it as a backup drive. While you can customize backup options in System Preferences, such as asking Time Machine to exclude certain folders, there's no action required on your part if you're happy with the default settings. The next time you plug in your drive, Time Machine will automatically set to work creating a backup.
Unless your drive is never going to leave your home or office, you should also consider its physical durability. Rugged, waterproof drives are a good option not just for surfers and BMX riders, as their marketing seems to suggest, but also for people who are carrying their drives to and from school or work, where they might occasionally get spilled on or dropped on the floor. (Check out our favorite rugged drives.)
Finally, you might want to consider how the drive will look when it's plugged into your Mac. Some drives come in a variety of colors. Many others feature copious amounts of aluminum and industrial-chic styling to match the design cues of your MacBook or iMac.
So, Which Drive Should I Buy for My Mac?
We've selected a host of our favorite drives up top; all were tested on both Windows and macOS systems. For more options, check out our main list of best external hard drives and our top picks for external SSDs.
Where To Buy
Best for Photographers, Videographers, and Travelers
Photo and Video Pros in the Field
Best for Mac Users Seeking Ruggedized Storage
Frequent Travelers, Value Seekers
Best for Outdoor Enthusiasts and Business Professionals
Best for Outdoorsy Mac Users
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This article was co-authored by Jeremy Mercer. Jeremy Mercer is the Manager and Head Technician at MacPro-LA in Los Angeles, CA. He has over ten years of experience working in electronics repair, as well as retail stores that specialize in both Mac and PC. This article has been viewed 383,748 times.
Usually, when you want to connect an external hard drive to your computer, you just plug it in and that's it. However, if you are using a Macbook Pro or any Mac computer, the hard drive must be formatted with a file system your Mac can support. Formatting the drive will erase all of the data on it. If the hard drive is pre-formatted as NTFS, like most hard drives in the market, the Mac OS X can only read data from it, not write any data on it.
Steps
Part 1 of 3:
Connecting the Drive
1
Plug the hard drive into the Mac using the cable that came with it. Most hard drives connect via USB, so you'll just need to plug the USB cable into an open port on your Mac. You'll typically find at least one USB port along each side of the Mac.
Some Mac-specific drives may come with a Thunderbolt or FireWire cable instead. If this is the case, you'll need to plug it into the correct port, or get an adapter if you don't have the proper port on your Mac.
Computer Repair Technician
Jeremy Mercer is the Manager and Head Technician at MacPro-LA in Los Angeles, CA. He has over ten years of experience working in electronics repair, as well as retail stores that specialize in both Mac and PC.
You can choose an external hard drive based on price or speed. Some external hard drives have HDD drives in them, which makes them a cheaper, slower option that has a lot of storage. There are also solid-state hard drives that cost a little more but are much faster. Make sure you have the right cords to connect the drive to your Mac.
2
Check for your drive on your desktop. If the drive is formatted and connected properly, it will appear on your Mac's desktop as a drive with a USB or Thunderbolt icon.
The drive icon may not appear on your desktop even though it is connected properly. You can check for the drive in the left frame of any Finder window, under the 'Devices' heading.
You can set drives to appear on your desktop by clicking the Finder menu, selecting 'Preferences,' and then checking the 'External disks' box.[1]
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Part 2 of 3:
Formatting a Drive
1
Open the Disk Utility. Most external hard drives are pre-formatted to work with Windows computers, but this severely limits their functionality on a Mac. If your new external drive is formatted for Windows, you'll be able to read from it but you won't be able to write to it. You can format it to the proper file system using Disk Utility.
On the Desktop, click the 'Go' menu, select 'Utilities,' and then 'Disk Utility.'
Formatting the drive will erase everything on it. This is fine for new drives, but if you're trying to use an older drive that already has files on it, you'll need to save them before you start formatting.
2
Select the hard drive from the left menu. You'll see a list of all of your connected drives in this menu. Select your new external drive from the list.
If you don't see your drive here, see the next section.
3
Click the 'Erase' button at the top of the Disk Utility window. This will start the drive formatting process.
This will erase everything on the hard drive, so make sure any important data has been backed up. If the drive is in Windows format, you can still copy the files you want to save to your Mac before formatting it.
4
Select 'ExFAT' from the 'Format' menu. This format is compatible with Mac OS X, Windows, and Linux, allowing you to move your hard drive easily between systems. unlike earlier versions of FAT, there are no practical limits on file size or volume size, which means you can use it on any size drive.
If you're only planning on using the drive with your Mac, select 'Mac OS Extended (Journaled).' This will allow you to take advantage of all of your Mac's features with the drive, such as Time Capsule.
5
Click 'Erase' to format the drive with the selected format. This is irreversible, and will erase all data that is currently on the drive. The time the format takes will vary depending on the size of the drive.
6
Try your newly-formatted drive. Once the drive has been formatted properly, it will appear on your desktop. Double-click it to open it, and you should be able to add file to it and remove files from it.
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Part 3 of 3:
Finding a Missing Drive
1
Ensure the drive is properly connected. Make sure that all of the cables are properly connected to the drive and to the Mac. If a cable has come lose, the drive will not appear.
2
Make sure the drive has enough power. Some external drives require a separate power connection. You may need to get dual USB cable. This cable has a single USB plug on one end that goes into the external drive, and then splits into two plugs that both get inserted into your Mac.[2]
4
Try different cables and ports. You may have a faulty USB cable, or one of the USB ports on your Mac may be malfunctioning. Try plugging the hard drive into a different USB port using a different USB cable.[3]
Click 'Run' to begin scanning the drive for errors.
Allow the utility to fix any errors it finds. This may allow you to start using the drive again. Be aware that if errors have appeared, this could be an early warning sign of impending disk failure.
6
Consider replacing the drive. All hard drives eventually fail. The probability that you hard drive will fail increases with each year that you use it. Even new drives fail at a rate that would surprise most people. If your drive is four years or older and isn't appearing no matter what you do, there's a very good chance that it's simply dead.
You can try plugging it into a different computer to see if it appears. If it's not appearing anywhere, it may be time for a new drive.
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Community Q&A
Add New Question
After formatting with Exfat, Will my HDD work on both Windows and Macbook?
Community Answer
I have an external hard drive that it is attached to the new Macbook pro via an adapter. How can I access the drive?
Community Answer
If it has the correct format, it will show up in you desktop. If it doesn´t show up in the desktop, check if the the option 'external drives' is checked in Finder Preferences, General.
Will this erase all of my files?
Community Answer
No. The contents will only be erased if you format or partition the connected hard drive.
How do I allow writing on an external hard drive?
Community Answer
This depends on the external hard drive. On drives, files follow some 'file format,' depending on the computer that set up the drive. Windows uses a format called NTFS. Mac can read files from this format, but it doesn't know how to write files to this format. You would need to reformat the drive in order to write to it. BEWARE! Reformatting a drive will delete all data from the drive. If you do reformat, you have options. The FAT format will allow read and write from anything and to anything, but the maximum size of files is 4GB. The exFAT format does not have the file size constraint, but it is less safe - it doesn't guarantee safe writing of files, creating the possibility of bad files.
If my hard drive is connected to my MacBook and I erase files off the laptop, are they also erased off the external drive?
Community Answer
It depends on the location of the file. Erasing a file from your internal hard drive (or 'off the laptop') will not affect any files on the external hard drive. If you actually erase a file directly from the external drive, then yes.
How do I safely exit from my external hard drive on my Macbook Pro?
Community Answer
Your external hard drive should appear in the Finder menu on the left under Locations. Click on the eject icon.
I am a student. Can I run SolidWorks on Windows from an external drive on my Mac laptop? If so, which external drive is compatible?
Community Answer
If you mean that you have used BootCamp to run Windows on your Mac laptop, then yes. All external drives should work provided that they have enough storage capacity. Make sure that the drive is formatted to Exfat.
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This article was co-authored by Jeremy Mercer. Jeremy Mercer is the Manager and Head Technician at MacPro-LA in Los Angeles, CA. He has over ten years of experience working in electronics repair, as well as retail stores that specialize in both Mac and PC. This article has been viewed 383,748 times.
Updated: October 28, 2019
Categories: MacBook
In other languages
Русский:подключить внешний жесткий диск к Macbook Pro
Português:Conectar um HD Externo em um Macbook Pro
Italiano:Collegare un Disco Rigido Esterno a un Macbook Pro
Español:conectar un disco duro externo a una Macbook Pro
Best Hard Drives For Macbook
Deutsch:Eine externe Festplatte an ein MacBook Pro anschließen
Français:connecter un disque dur externe à un Macbook Pro
Tiếng Việt:Kết nối ổ cứng gắn ngoài với Macbook Pro
ไทย:เชื่อมต่อ External Hard Drive กับ Macbook Pro
Hard Disk Definition
Nederlands:Een externe harde schijf koppelen aan een Macbook Pro
हिन्दी:एक्सटर्नल हार्ड ड्राइव को मैकबुक प्रो से कनेक्ट करें
Türkçe:Haricî Sabit Disk Macbook Pro'ya Nasıl Bağlanır
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