If you’re looking for the best external hard drive to backup your Mac with Time Machine or just need more storage space, we’ve looked at the best Mac compatible external drives of 2023.
Macs are increasingly difficult to upgrade the storage internally and using an external hard drive is a quick, easy and cost effective solution.
In fact with the latest Apple Silicon M1 & M2 Macs such as the M1 MacBook Pro, M2 MacBook Pro and Mac Studio, it’s impossible to upgrade the hard drive internally so external hard drives are your only option.
However, the external hard drive landscape and connection port technologies is constantly changing and it can be difficult to know where to start when buying one.
- HDD vs SSD vs Thunderbolt
- What’s The Best External Hard Drive For M1 & M2 Macs?
- 1. Seagate Ultra Touch HDD (Best Overall)
- 2. WD My Passport For Mac (Best For Time Machine)
- 3. Transcend StoreJet M3 (Best For Photographers)
- 4. WD My Book Desktop (Best Desktop Drive)
- 5. Samsung T7 Portable SSD (Best SSD)
- 6. SanDisk Professional Pro-G40 SSD (Best Thunderbolt Drive)
- 7. WD My Book Duo Desktop RAID (Best For Security)
- 8. WD My Book Thunderbolt Duo (Best RAID Drive)
- 9. OWC ThunderBay 4 Raid (Best For Storage Size)
- 10. G-Tech Thunderbolt 3 (Best Looking)
- Best External Hard Drives For Mac Compared
- What External Hard Drive Does Apple Recommend?
- Do All External Hard Drives Work With Mac?
- How To Choose An External Hard Drive For A Mac
HDD vs SSD vs Thunderbolt
Before we dive in, it’s important to understand that there are basically three types of external drive on the market:
- HDD drives which are the cheapest and have moving parts inside (also known as mechanical drives) which we’ve mainly focused on in these reviews.
- SDD drives which are Solid State Drives which have no moving parts inside so they are faster but more expensive.
- Thunderbolt drives which are the same as SSD drives but are even faster (but a lot more expensive) due to Thunderbolt transfer speeds of up to 40GB/s.
The great thing for Mac users is that all of these external storage solutions have never been cheaper and storage sizes have never been bigger than they are in 2023.
Less than a decade ago, you would have paid several hundred dollars for a chunky hard drive with just a few Gigabytes (GB) of storage space on.
Now you can get up 5 Terabytes (TB) of portable storage (that’s a whopping 5000 GB) for little more than $100 from some manufacturers.
What’s The Best External Hard Drive For M1 & M2 Macs?
All external hard drives work with Apple Silicon M1 Macs & M2 Macs as long as they have a USB-C or Thunderbolt connection.
The latest M1 & M2 MacBook Pros and Mac Studio have Thunderbolt 4 ports and so in terms of speed and compatibility, the best external hard drives for M1 and M2 Macs are Thunderbolt hard drives.
There are currently a limited number of Thunderbolt only external hard drives on the market although we ranked the SanDisk Professional Pro-G40 SSD is currently the best Thunderbolt drive for M1 & M2 Macs.
With this in mind, here then are the best external hard drives for Mac of 2023 in order of ranking.
1. Seagate Ultra Touch HDD (Best Overall)
Seagate have always made some of the cheapest and most reliable external hard drives and the Seagate Backup Plus wins the award for the best overall external hard drive for Mac.
You can pick up a 2TB Seagate Ultra Touch for just $79.99 which is one of the cheapest external hard drives for Macs you’ll find.
The Seagate Ultra Touch HDD replaces the original version and now features a USB-C connection with capacities of 2TB, 4TB or 5TB.
The Seagate Ultra Touch HDD is portable and light enough to put in your coat pocket or backpack. The smaller capacity models are available in white with the bigger ones available in grey.
The Seagate Ultra Touch HDD is ready formatted for use on Macs and Time Machine ready for instant backups as soon as you plug it into your Mac.
It also comes with Seagate Dashboard backup software which has always been a bit bloated and hard to customize backups with on a Mac but there’s really no need to use it if you’re using Time Machine for your backups.
Although it’s not drop resistant, you can also get a shockproof carry case for it. Users in the USA can also take advantage of Seagate Rescue Services to try and recover data if the drive gets damaged.
You should get read-write speeds of around 130MB/s which isn’t bad for a portable HDD although those that want speed should be looking at SSD or Thunderbolt drives instead.
- Excellent value
- Ready formatted for Macs
- Works with Thunderbolt ports via USB-C
- Time Machine ready
- Seagate backup software is bloated on Mac
- Slow compared to SSD drives
2. WD My Passport For Mac (Best For Time Machine)
We think the Western Digital 5TB My Passport For Mac is the best external hard drive for Mac for Time Machine of 2023 due to a solid combination of reliability, value for money and portability.
For those with portable MacBooks, we think the WD My Passport For Mac is certainly the best external hard drive for the MacBook Pro and MacBook Air.
The WD My Passport For Mac is ready formatted for use on Mac, Time Machine ready and small enough to fit in your coat pocket.
With a 3 year warranty and big enough to backup all Mac hard drives, if you need a fast, reliable, value for money backup solution for your Mac, the WD 5TB My Passport is an an excellent external hard drive.
The WD My Passport for Mac supports USB 3.0/Thunderbolt connections but it will also work with older USB 2.0 connections which makes it compatible with both older Intel Macs and newer Apple Silicon M1 & M2 Macs.
The main drawback of Western Digital products is that the the WD Discovery software that can be used with it does not work natively on Apple Silicon M1 and M2 Macs.
The WD Discovery software still works on M1/M2 Macs using Rosetta but the performance can be unstable and may lead to crashes and bugs when trying to navigate or administer the device.
If you don’t want to use the WD Discovery software however (which you really don’t need to unless you want to set a password or download your social media data) the WD My Passport also works perfectly well with M1/M2 Macs.
We recommend paying that little extra for the 5TB which is the biggest version available in the My Passport Range which ranges from 500GB to 5TB.
If you’re going to carry it around a lot, we also recommend getting a proper carry case for it too.
You can alos check out our full WD My Passport For Mac Portable Hard Drive review for a more in-depth look.
- Very reliable
- Works with both older Intel Macs and M1 & M2 Macs
- Ready formatted for Macs
- Good value for money
- Supports both Thunderbolt 2 and 3
- 3 Year Warranty
- Limited to maximum of 5TB
- WD Discovery software not compatible with M1 & M2 Macs
3. Transcend StoreJet M3 (Best For Photographers)
The main selling point of the Transcend StoreJet M3 is that it’s incredibly tough.
For those that intend to use a storage or backup device on the move such as photographers, we think it’s the best external hard drive for photographers on Mac due to its incredible durability.
In fact, the Transcend StoreJet M3 is military drop tested with an advanced 3 stage shock protection system and an incredibly strong anti-shock rubber outer case.
The Transcend StoreJet M3 also comes with its own software that can be used for one-touch backups.
Just press the button on the Transcend and the software will automatically backup although it also works with Time Machine.
The Transcend StoreJet M3 also comes with an extra USB cable to connect to a second USB port in case your Mac can’t provide enough power for it from one connection although most Mac users shouldn’t need this.
If you’re going to using an external storage device outside, the Transcend StoreJet M3 is a good choice but note that it only comes in a 1TB and 2TB version – there’s nothing bigger.
To enhance protection, you can choose from a range of carry cases too.
- Incredibly strong and durable
- One touch backup system
- USB 3.0 connection
- Encrypts files and folders
- No Thunderbolt port
- Limited to maximum 2TB
4. WD My Book Desktop (Best Desktop Drive)
If you don’t need a portable external drive and are happy to simply have something bigger on your desktop, then look no further than the WD My Book Desktop.
We’ve used WD My Book Desktops for over 10 years and never had a problem and would not hesitate to recommend it still.
Unlike the portable version, the WD My Book Desktop has its own power supply which you connect to the mains so it doesn’t draw any power from your Mac.
It has a USB 3.0 connection port but also works with USB 2.0 ports. Unfortunately it doesn’t have a USB-C/Thunderbolt port although you can use a USB 3.0 to Thunderbolt converter cable with it.
The WD My Book Desktop also comes with its own WD Discovery Backup Software which is straightforward but you really don’t need it if you use Time Machine or another backup software.
As revealed in the WD MyPassport review however the WD Discovery software does not work natively on Apple Silicon M1 & M2 Macs.
The WD Discovery file management software still works on M1 & M2 Macs using Rosetta but the performance isn’t as good and may lead to crashes and bugs when performing backups.
If you don’t want to use the WD software however, the WD MyBook Desktop works perfectly well with M1 & M2 Macs.
For security, the WD MyBook Desktop also features 256bit AES hardware encryption that password protects your data.
The WD My Book Desktop is available in 3TB going up to 10TB.
- Very reliable
- Ready formatted for Macs
- Encryption password protected
- WD Discovery software doesn’t work natively on M1 & M2 Macs
- Works with both USB 2.0 and USB 3.0 ports
- No Thunderbolt or USB-C port
5. Samsung T7 Portable SSD (Best SSD)
SSD drives usually offer the poorest value for money in terms of dollars per TB.
They are however extremely fast and silent compared to solid state drives because like your Mac’s internal hard drive, they have no moving parts.
However, in our opinion, the best consumer priced SSD external hard drive for Mac you can currently get in 2023 is the Samsung T7 Portable SSD.
The Samsung T7 Portable SSD is an SSD external hard drive for Mac with read-write speeds of up to 1050 MB/s which is at least twice as fast as most mechanical drives.
It’s incredibly small being not much bigger than a credit card and weighs just 58 grams. It works on Mac, PC and Android devices but note that it’s not ready formatted for macOS out of the box.
The Samsung T7 is shock resistant and there’s less chance of it burning-out that a mechanical hard drive because there are no moving parts.
In fact, Samsung claims it can withstand 1500G of G-force equivalent to being dropped from 6.5 feet.
The Samsung T7 SDD has a USB-C port which means you can use a Thunderbolt 3 cable with it although USB-C can’t quite deliver Thunderbolt 3 transfer speeds.
For that you’ll need the SanDisk Professional Pro-G40 SSD (see review below) which supports full Thunderbolt speeds almost 3 times faster than the Samsung T7.
The Samsung T7 also comes with a USB-C to USB-A cable in the box for backwards compatibility.
If you’re looking for incredibly fast transfer speeds, the latest in SSD technology, portability and durability, the Samsung T7 is the best external SSD drive for Mac.
- Super fast SSD drive technology
- Silent hard drive
- Incredibly small and compact
- Does not get warm
- Shock resistant
- Great compatibility with the latest M1 & M2 Macs
- Price compared to external mechanical HDD drives
- Samsung software that comes with it
- Doesn’t support full Thunderbolt speeds
6. SanDisk Professional Pro-G40 SSD (Best Thunderbolt Drive)
The SanDisk Professional Pro-G40 SSD was recently released by SanDisk and is the best external Thunderbolt drive for Mac.
Because it uses Thunderbolt rather than USB-C and you will enjoy read-write transfer speeds of at least 2500MB/s which is roughly twice as fast as most USB-C SSD drives.
Note that although it will work with Thunderbolt 4 connections on the latest Macs, it doesn’t have full Thunderbolt 4 support but you’ll get pretty close to the maximum Thunderbolt 3 speeds available.
The SanDisk Professional Pro-G40 SSD is therefore aimed at creative users such as video editors and graphic designers that transfer several GB of data regularly.
The SanDisk Professional Pro-G40 SSD is surprisingly durable too with an IP68 rating for water resistance and drop resistant up to 3 meters according to SanDisk.
The SanDisk Professional Pro-G40 SSD is available in 1TB, 2TB and 4TB versions with the biggest version costing around $799.
However, because it’s a Thunderbolt SSD with incredibly fast transfer speeds and impressive durability, the SanDisk Professional Pro-G40 SSD is worth it for those that don’t have time to hang around.
- Supports Thunderbolt for transfer speeds of over 2500MB/s
- IP68 rated with impressive durability
- Also works with USB-C
- No Thunderbolt 4 support
7. WD My Book Duo Desktop RAID (Best For Security)
If you want the biggest and best encrypted external hard available on the market in 2023 at consumer prices, then go for the WD My Book Duo Desktop RAID.
The WD My Book Duo Desktop RAID is the best external RAID hard drive for Mac and consists of two drives in one enclosure which can be combined as RAID drives to double capacity and speed.
The biggest 36TB drive for example is actually two 16TB WD Red HDDs packed together in one casing.
By combining both drives in one, it offers super fast transfer speeds of around 324 Mbps.
The WD My Book Duo Desktop is the cheapest and most reliable external hard drive for Mac which allows you to choose RAID disks.
RAID (Redundant Array of Independent Disks) is just a way of combining two hard drives into one super hard drive.
You can choose between using both drives as RAID 0 (very fast) or RAID 1 (more secure) or divide them both using JBOD. By default, it is configured in RAID 0 but you can easily change it to RAID 1.
If you want to take out or replace on the drives you can also push down on the top of the enclosure and the lid will pop up allowing you to remove the drives.
However, note that you can only use the same drives with the same enclosure.
If the enclosure fails for any reason, you can’t just pop out the hard drives and pop them in a new one to save them as each hard drive has a unique encryption key for each enclosure. Enclosure failure is very rare though.
WD SmartWare will automate backups for you and even integrates with DropBox for cloud backups too but you can use Time Machine or any other Mac backup software.
Note that this particular WD hard drive does not come ready formatted for Mac but you can easily format it for Mac in a few minutes using Disk Utility in macOS or by following these instructions.
Although it’s a bit on the pricey side, considering you’re getting two Western Digital 8TB hard drives in one enclosure, it’s actually a very good deal.
If 16TB is too big, you can also buy it in models ranging from 4TB to 24TB.
It’s also surprisingly quiet for such a large hard drive and there’s no noisy fan as it’s cooled from the bottom vents with warm air flowing out of the top vents.
- Very reliable
- Surprisingly quiet for such a big drive
- Incredibly fast data transfer rates
- Huge storage capacity
- No Thunderbolt port
8. WD My Book Thunderbolt Duo (Best RAID Drive)
Thunderbolt 3 drives are still pretty expensive in 2023 and USB 3.0 offers better value for money with transfer speeds of up to 5 Gbps.
However, if you want a Thunderbolt 1 (10 Gbps) or a Thunderbolt 2 (20 Gbps) external drive for Mac and are willing to pay that bit extra, the WD My Book Thunderbolt Duo is an impressive piece of kit.
The WD My Book Thunderbolt Duo is designed specifically for Thunderbolt 1 connections delivering transfer speeds of up to 10Gbps.
Like the WD My Book Duo, it’s actually two drives combined and has two Thunderbolt connections so that you can access both drives at once if you need to (although note that it only comes with one Thunderbolt cable).
Outside of SSD drives, the WD My Book Thunderbolt Duo is probably the quietest external hard drive for Mac we’ve tried and is ready formatted for use on Mac. It’s also RAID 0 ready although it can be configured for RAID 1 too.
Note though that if just one drive is configured as RAID 0 and the other as RAID 1, you will lose any data on the RAID 0 drive if anything goes wrong so we strongly recommend using RAID 1 on both which treats them both separately even if it does deliver slower performance.
The WD My Book Thunderbolt Duo is only available in 4TB size though.
If you want a reasonably priced Thunderbolt external drive for Mac that quiet and reliable, don’t look any further than the WD My Book Thunderbolt Duo.
- Very reliable
- Thunderbolt port
- Very quiet external hard drive
- Only goes up to 4TB
9. OWC ThunderBay 4 Raid (Best For Storage Size)
The OWC ThunderBay Raid is pretty much the fastest and biggest external hard drive for Mac you can get with a maximum of a massive 40TB of storage.
There’s an even bigger model the ThunderBay Raid 8 which goes up to an incredible 128TB.
It’s also one of the only external hard drives to support Thunderbolt 3 which gives incredible top speeds of 1.3Gbps although in reality, you’ll probably get sustained speeds nearing to 827Mbps which is about as fast as it gets for an external mechanical hard drive at the moment.
The OWC ThunderBay also supports RAID 0, 1, 4, 5 and 1+0 meaning you can use each drive separately or combine them for fastest speeds.
The OWC ThunderBay Raid is however one of the most expensive external hard drives you can get for Mac with the largest 40TB of storage costing well over a few thousand dollars.
The OWC ThunderBay is mainly aimed at video editors, enterprises and small businesses that need massive storage and ultra fast rock solid performance.
The Thunderbolt 2 connection is enough for video editors to edit and stream 2K or 4K footage from although note that it doesn’t support Thunderbolt 3.
Like all OWC external drives, the OWC ThunderBay 4 RAID comes with a 5 year warranty which is the longest you’ll find for a quality external hard drive on Mac.
Overall, the OWC ThunderBay Raid is easily the biggest and most reliable external storage drive for Mac available so if you need some serious storage space, it’s the ultimate external hard drive for Mac.
If there’s no availability on Amazon, you can also buy the OWC ThunderBay 4 RAID direct from OWC too.
- Offers the biggest storage space of any external hard drive
- Thunderbolt 3 compatible
- 5 year warranty
- Not formatted out of the box for Macs
10. G-Tech Thunderbolt 3 (Best Looking)
G-Tech is a brand of Western Digital aimed specifically at the Macintosh and creative professional market.
G-Tech drives are already formatted to use with Macs (although you can re-format them for use with Windows too).
Like most Western Digital products, G-Tech products are reliable, solid and have a more aesthetically pleasing design than Western Digital’s MyBook range.
The G-Tech 4TB Thunderbolt 3 drive can be daisy chained to up to 5 drives and is available from 4-12TB.
If you daisy chained 5 12TB drives that gives you a massive 60TB of very high speed storage space.
The Thunderbolt 3 claim is a bit misleading however. Although G-Tech drives have a Thunderbolt 3 and USB-C port with support for USB 3.1 Gen 1, the reality is it can’t achieve the maximum transfer speed offered by Thunderbolt 3.
This is because inside it’s still only a 7200RPM SATA hard drive which is only capable of delivering transfer speeds of up to 180MB/s whereas Thunderbolt 3 can go up to 250MB/s.
If you really want to get anything close to Thunderbolt 3 transfer speeds, you’ll be better going with the Samsung X5 SSD drive which is more expensive and has less storage space but because it’s a Solid State Drive (SSD), can achieve much faster transfer speeds.
- Made by Western Digital
- Supports Thunderbolt
- 5 year warranty
- Supports daisy chaining
- Not an SSD so doesn’t fully achieve Thunderbolt 3 speeds
Best External Hard Drives For Mac Compared
Although we can’t compare all the drives reviewed here, here’s a side-by-side comparison of our top six external drives for Mac to see how they measure up against each other.
What External Hard Drive Does Apple Recommend?
The only officially Apple endorsed hard drive is the Apple Airport Time Capsule but it was discontinued in 2018.
Time Capsule worked over your WiFi connection so backups were performed wirelessly when used with macOS Time Machine.
However, we don’t recommend trying to get an Apple Airport Time Capsule for a couple of important reasons.
The main reason is that it’s discontinued by Apple and nowadays you can only buy refurbished versions of it.
The other reason is Airport Time Capsule was expensive compared to other hard drives and you don’t get many terabytes for your money.
Finally, backing-up via WiFi is also much slower than using an external hard drive connected with either a USB-C port or Thunderbolt connection.
All of the hard drives we’ve reviewed here are much better alternatives to Airport Time Capsule as an external hard drive solution.
Do All External Hard Drives Work With Mac?
Almost all external hard drives work with Macs but there are a few important things to be aware of to avoid disappointment.
Most external hard drives are already formatted to work out of the box to plug-and-go with macOS although some require formatting first depending on whether you want to use them on Apple only products or transfer files between macOS and Windows.
Don’t let this put you off non ready for Mac formatted hard drives however as it’s very easy to format an external hard drive for Macs.
Most external hard drives nowadays use USB-C ports (which are confusingly subdivided into USB 3.1 Gen 1, Gen 2 and Gen 2×2) and USB 4.0 to connect to PCs and Macs.
However, most Macs since around 2017 have Apple Thunderbolt 3 and Thunderbolt 4 ports which support more than twice the transfer speed than most USB-C can ports can (except USB 4.0 which can transfer data at the same speed as Thunderbolt 3 and 4 which is 40Gb/s).
The fastest and arguably the most Mac compatible external hard drives are therefore dedicated Thunderbolt hard drives but they are also the most expensive.
Note that there’s no difference in transfer speeds between Thunderbolt 3 and Thunderbolt 4 but Thunderbolt 4 ports have stricter standards with slightly more flexibility and power when it comes to connecting external monitors.
You can however plug any USB-C external drive into a Thunderbolt connection as they use exactly the same port but you won’t enjoy the incredibly fast transfer speeds of up to 40Gb/s that Thunderbolt is capable of.
In some cases, you won’t even enjoy the maximum speed advertised by the manufacturer.
For example, the SanDisk Extreme Pro SSD drive for claims to offer transfer speeds of 2000MB/s via a USB-C standard known as USB 3.2 2×2 which equals 16Gb/s.
However, Mac users will get less than half these speeds with USB 3.2 2×2 connections due to technical differences in the way Thunderbolt and USB 3.2 Gen 2×2 work.
For more on this check out our look at the differences between Thunderbolt vs USB-C.
How To Choose An External Hard Drive For A Mac
With internal Mac hard drives becoming increasingly difficult and expensive to upgrade internally, an external hard drive provides the perfect solution.
However, the technology of external hard drives and the connection port types on Macs have changed a lot in the past few years so it can be quite confusing knowing what to go for and how they perform with Macs.
Going for the cheapest hard drives with the most storage space is definitely a false economy in our experience and the loss of your precious data can be priceless.
Generally, the best external storage devices for Mac users fulfill similar criteria to those that are best for PCs but there are some specific things that make some more Mac compatible than others.
Here then are some essential points to consider when buying and using an external hard drive on Mac to help you decide which one is best for you.
Reliability is probably the most important consideration when purchasing an external hard drive for your Mac.
The worse thing that can happen to an external storage device is disk failure.
When this happens, you’ve usually lost everything stored on it which can be a total disaster if you’ve got precious family photos or important documents on there.
Manufacturers rate the reliability of their hard drives with “Annualized Failure Rates“. However, these figures should be taken with a pinch of salt.
Although manufacturers sometimes quote an Annualized Failure Rates of less than 1% (AFR is a percentage of total hard drives sold that fail annually) any figures on reliability aren’t worth basing your decision on in our opinion because everyone uses hard drives in different ways.
For example, those that leave their external hard drives switched on all the time or use it constantly for video editing are going to experience more frequent failures than those that only switch them on occasionally for backups.
Most manufacturers will guarantee at least two years of reliability and the best manufacturers like Western Digital (WD) offer 3 years and OWC offer five year guarantees although in reality, all external hard drives should outlast this with moderate use.
Of course, any such guarantees are little compensation in terms of your precious data in the case of failure. You will have lost all of your files anyway but at least you’ll get a free replacement from the manufacturer.
If you want to learn more about why hard drives fail, you can find an interesting look at hard drive reliability here.
Buy A Decent Brand
This is probably the most important piece of advice when buying an external hard drive.
There is definitely a difference between established brands and lesser known newcomers to the market.
Until recently, the general consumer external hard drive market was dominated by two big players – Western Digital and Seagate – both of which have been in the business over 20 years.
However, more recently Samsung and SanDisk have become increasingly popular external hard drive manufacturers.
At MacHow2, we use Western Digital (WD) external hard drives on a regular basis and would not hesitate to recommend them such as the extremely reliable WD My Passport range of external hard drives.
Note that Hitachi drives are now owned by Western Digital so if you buy a Hitachi external hard drive, you’re effectively getting a Western Digital product.
There are of course other brands such as LaCie, Fujitsu and Toshiba but they’re considerably behind the big brands when it comes to external hard drive market share and reputation.
Schedule Backups & Usage
Do not use your external hard drive more than is absolutely necessary.
If you have it switched on all day, and particularly if you keep accessing it all day, it’s going to burn out far more quickly than if you just switch it on once daily or weekly to make backups.
Quite simply, the more you use an external hard drive, the quicker it will eventually fail.
Use A Second Backup Solution
If you’re using an external hard drive on your Mac for performing backups, you should also consider using a second backup solution.
The chances of two external hard drives failing at the same moment are extremely slim so if your backups are really important, using two drives is the best thing you can do for backups.
If you don’t want to purchase a second drive, alternatively you can make sure you’re using a cloud backup solution in tandem with your external hard drive.
The WD My Book Duo for example also allows you to backup to it’s own Cloud service Western Digital MyCloud although this of course costs extra.
For Mac and iOS users however, the easiest solution is to backup using Apple’s iCloud alongside your external hard drive.
You get 5GB of free online storage with iCloud with plans starting at just $0.99 per month for up to 50GB of storage.
Get A Power Surge Protector
One thing that can instantly destroy your hard drive is a power surge in your home or office electricity supply.
A common occurrence with cheaper brand external hard drives is that the inverter inside fails which basically allows too much power to short-circuit and destroy the hard drive.
In these cases, a surge protector won’t help you which is another reason why we only recommend buying an external hard drive from a reputable brand.
However, you can easily protect against this with a cheap Surge Protector Power Strip which is well worth the investment (for your Mac too).
Never Move An External Drive When Its Switched On
External Mechanical HDD drives have moving parts which read the magnetic surface of the drive.
It’s therefore important never to move an external hard drive when it is switched on.
There is a danger that the read/write heads can move and make contact with the hard drive in which case, it will break immediately.
The only way to avoid this is to buy a Solid State Drive (SSD) which have no moving parts although they are more expensive and have less storage capacity than HDD drives.
The internal hard drive on all new Macs are SSD drives which is why it’s perfectly safe to carry around a MacBook even when it’s switched-on and not worry about damage from movement.
Buy The Most Storage Space You Can Afford
External hard drives now offer massive amounts of storage space and the starting point in most external hard drives is now generally at least 1 Terabyte or more.
1 TB equals 1000GB and is roughly equivalent to 488,000 photos and 220 full length movies so a 5TB hard drive could be enough for a lifetime of photos or music for most people (see the table below).
There’s no right or wrong answer when it asking yourself “how much storage storage space do I need?”.
Our advice is simply to buy the biggest you can afford.
Cloud storage solutions such as iCloud and OneDrive are certainly reducing the need for physical storage but the bigger your external storage device is, the more it can grow with you.
As photos and videos increase in size (most digital cameras and even iPhones can film in 4K for example which eats massive amounts of hard drive space) the bigger the better.
Desktop vs Portable External Drives
There are generally two types of external hard drives for Mac:
- 3.5 inch desktop drives that have their own mains power source
- 2.5 inch portable external drives that take their power from your Mac
Portable drives will easily fit in your jacket pocket but have less storage capacity.
Desktop drives are less portable but the biggest ones offer more than 50TB of storage.
SSD vs Mechanical Drives
The cheapest and most popular hard drives are still mechanical HDD drives which means they have moving parts inside.
Because they have moving parts however, they can can deteriorate and break more easily.
Solid State Drives have no moving parts and are therefore less likely to break and they’re incredibly fast but there are less available and are expensive for the little storage space they offer.
Most Thunderbolt external hard drives also use SSD drives inside.
There’s no doubt that SSD drives will eventually replace mechanical drives in the external hard drive market but the economies of scale still quite aren’t there yet.
All new Macs since 2012 (except some iMacs, Mac Minis and non-retina MacBook Pros) including Apple Silicon M1/M2 Macs, have internal SSD hard drives fitted as standard and anyone that’s used older Macs with mechanical internal hard drives will tell you how much faster and efficient SSD drives are.
SSD drives are also silent and run cooler compared to mechanical drives which whir and buzz due to the drive spinning which also creates more heat.
There are also some hybrid drives that are a mix of solid state and SSD drives although these are less common.
Currently, we rate the best SSD external hard drive for Mac as the Samsung T7 Portable but you only get 2TB.
You can learn more about Solid State Drives in our guide to the best external SSD drives for Mac.
External Hard Drive Speeds
The speed of backups or data transfer from your Mac to your hard drive depends on two things – the connection port type (see below) and the hard drive’s physical speed denoted in Revolutions per Minute (RPM).
Most mechanical HDD external hard drives spin at 5400RPM but there are some faster high-end drives that are 7200RPM.
A 7200RPM drive will be faster than a 5400RPM drive because the drive revolves faster and therefore can be read by the drive head quicker.
If you’re connecting a 7200RPM hard drive via a super fast Thunderbolt or USB 3.0 connection, then you’ll enjoy the hard drive’s maximum transfer speed.
However, a 7200RPM mechanical drive can’t achieve anything near Thunderbolt 3 speeds.
A good example is the G-Tech Thunderbolt 3 external drive which has a 7200RPM mechanical drive but still can’t achieve the maximum transfer speed of Thunderbolt 3.
The G-Tech 2TB Mobile SSD can however reach maximum speed when connected to a Mac because it’s a Solid State Drive (SSD).
At the other end of the scale, if you’re connecting with an older Mac via a USB 2.0 or Firewire port, then your connection cable won’t even be able to deliver the maximum speed of the hard drive so you might as well save some money and get a 5400RPM with greater capacity than a fast drive with less capacity.
If you’re looking for maximum transfer speeds, by far the fastest external hard drives are dedicated Thunderbolt drives which can transfer at speeds of up to 2800MB/s.
External Hard Drive Connection Ports & Speeds
The business of external hard drive connection ports on Macs can be extremely confusing as USB-C standards constantly change and Apple seemingly keeps changing ports on every new generation of Mac.
Data transfer speeds are measured in “Megabits per second” (Mbps) or “Gigabits per second” (Gbps). 1000 Mbps equals 1 Gbps.
|Firewire 400||400 Mbps|
|USB 2.0||480 Mbps|
|Firewire 800||800 Mbps|
|USB 3.0||5 Gbps|
|USB 3.1||10 Gbps|
|USB-3.2 Gen 2×2||20 Gbps|
|Thunderbolt 1||10 Gbps|
|Thunderbolt 2||20 Gbps|
|Thunderbolt 3/4||40 Gbps|
All new Macs since 2012 have ditched Firewire in favor of Thunderbolt 3 connections offering staggering maximum data transfer speeds of up to 40 Gigabits per second (Gbps).
The latest Apple Silicon M1 & M2 MacBook Pro and Mac Studio have Thunderbolt 4 ports which offers the same speed as Thunderbolt 3 but more power when it comes to driving external monitors.
There are now an increasing number of Thunderbolt external drives on the market which are the fastest external drives for Mac you can get.
However, it is still USB-C connections that are used by most external drives.
USB-C ports are the same size as Thunderbolt and are interchangeable with Thunderbolt cables and devices .
However, USB-C does not offer the same speeds as Thunderbolt.
Confusingly, USB-C is divided into different standards such as USB 3.0, USB 3.1 Gen 1, USB 3.2 Gen 1, USB 3.2 Gen 2 and more recently USB 3.2 Gen 2×2 and USB 4.0.
The problem for Mac users is the latest USB 3.2 Gen 2×2 standard does not deliver maximum speed when connected to a Mac via a Thunderbolt port.
The reasons for this are complex but have caused a lot of confusion for Mac users that have bought USB 3.2 Gen 2×2 drives.
Thunderbolt 1, 2, 3 & 4 / USB-C
Since 2012, new Macs have Thunderbolt connections. Thunderbolt replaces the older Firewire connections and is now standard in all new Macs.
Most Macs from late 2016 and 2017 onwards have Thunderbolt 3 connections which offers speeds of up to 40 Gbps per second.
This is incredibly fast and easily allows you to edit video from your Mac as if it were on your Mac’s internal hard drive or even connect an 8K external monitor to.
Thunderbolt drives are commonly used by video editors and other creative professionals that need to transfer huge video or graphic files quickly.
Thunderbolt is great for those in creative industries such as video editing, music production and graphic design that have to handle large files such as RAW photos or high resolution 4K or even 8K videos that soon eat up valuable disk space.
Thunderbolt has been developed by Intel and Apple but uses the same connection port and cable type as USB-C which was developed separately by the USB Implementers Forum.
If you’re backing up large amounts of data, a Thunderbolt compatible external hard drive is definitely worth the investment because it makes backups much quicker.
Or if you’re planning on regularly transferring or backing-up 8K video, a Thunderbolt connection makes creating backups and editing in real-time from an external hard drive much quicker.
Macs before 2012 also have Firewire (400 and 800) ports but this standard is gradually being phased out and we don’t recommend getting a Firewire external hard drive.
Apple has replaced Firewire ports on all Macs made after 2012 with Thunderbolt ports.
The majority of manufacturers that still produce Firewire drives are not established brands either and therefore reliability may also be an issue.
However, if a Firewire port is important for you, we can recommend the well-respected and reliable OWC range of Firewire drives for Mac which support both Firewire and USB 3.0.
Note that if the external hard drive has a Firewire connection but you only have a Thunderbolt connection port on your Mac, you can use a Firewire to Thunderbolt adapter cable to connect it to your Mac although transfer speeds will be at Firewire speed, not Thunderbolt speed.
External Hard Drive Formats
You can easily format an external hard drive on a Mac using the free Disk Utility tool in macOS.
The format you choose will depend on what version of macOS you are using and whether you plan to use the drive with just Macs or both Macs and PCs.
If you want the drive to work with both Mac and Windows PCs then you need to format it in the exFAT or FAT32 format which works with both machines.
FAT32 however is limited to file transfers of 4GB so almost all drives that are to be used with both macOS and Windows need to be formatted in drives in exFAT format.
If you’re only going to use the drive with Macs using macOS High Sierra or later, then Apple’s APFS format is the best format to use.
Mac Backup Software
This could be an article in itself but we have absolutely no problem using Apple’s Time Machine software for backing up Macs and strongly recommend using it.
Time Machine is free in macOS, it’s quick and it’s easy to use. If anything happens to your hard drive, everything on your Mac including setup and configuration is saved in Time Machine.
Just plug Time Machine in case of data loss, operating system problems or plug it into a new Mac if your hard drive failed, and you can instantly roll back to the last working version of your Mac with all your files and folder.
Most external hard drive manufacturers also include their own backup and management software but they can be un-intuitive, inflexible and you really don’t need them.
Seagate’s Dashboard software for example is quite bloated and doesn’t make it easy to customize backups. WD’s Discovery software is also unreliable with the latest M1 and M2 Macs.