How to Choose an External Hard Drive

When it comes to learning how to choose an external hard drive, you need to consider what you want to do with the drive, how fast you need to be able to access the data on it, and how much you have to store on it. There are external hard drives with plenty of physical protection against the elements, external SSDs that give you super-fast data transfer, and huge external hard drives that are better for long-term backups. The best external drives often tick most of those boxes.

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If it's not obvious what kind of external hard drive you need, or you need something that can do a little of everything, here are some more in-depth tips on how to choose an external drive.

Storage capacity

Arguably the most essential specification to consider when buying an external drive is storage space. It does no good to buy a high-speed device with encryption and remote access if it&#;s not big enough to store all your data. You also don&#;t want to pay through the nose for a drive you&#;ll never even come close to filling.

What size of external drive is best? That depends on you.

If you want a device that&#;s good for transferring documents, photos, or other media from one device to the other, or just want a few tens of gigabytes of space to transfer files from system to system, a USB flash drive like the Corsair Survivor Stealth, might be a good idea. They're just $25 and give you 64GB of storage, which is enough to easily transfer thousands of photos or a few hundred videos between devices.

If you need something with a few terabytes of space but aren't too concerned about speed, then Western Digital's My Passport Ultra is a great drive with decent performance and multiple terabyte capacities. It's great for acting as a longer-term backup for your photos and videos, or transferring thousands of them from device to device.

If you need the ultimate in capacity, then look for the Western Digital My Book Duo. It's more NAS than external hard drive, but with 10s of terabytes of storage space, it's all the space you'll need for just about anything.

SSD vs. HDD

External drives are served up in two flavors: HDDs and SSDs. They both do things quite differently, but at the core of it, SSDs are faster than HDDs. They're more expensive, too.

HDDs (hard drive disk) use spinning magnetic disks to store data. Read/write heads change this data as necessary, so you hear their iconic spinning sounds. SSDs (solid-state drives) use tiny gate transistors in cells that can flip on or off based on electric pulses. They have no moving parts, hence the name.

SSDs are significantly faster than HDDs in many instances, but they get very expensive. HDDs are cheaper, but also larger, slower, and more easily damaged. For external drives, you'll get the fastest and more durable drive out of an SSD, like the excellent Samsung T5.

Transfer speed

The biggest external hard drives aren't always the best drives you can buy. Transfer speed is incredibly important, too. If you transfer files back and forth to an enormous drive regularly, you don&#;t want to wait forever for the transfer to complete.

Two main factors play a role in how fast your drive can operate: The underlying storage technology and the connector it uses.

Although some drives are faster than others, in general, SSDs can process data faster than HDDs. External SSDs tend to be more expensive than their HDD counterparts and often have less storage capacity. You don&#;t need one or the other, as there are larger SSDs you can buy for a premium price.

In terms of the connection between your external drive and your PC or mobile device, there are several standard options to consider. Most drives today use a USB interface, but the most recent generations have some distinct differences -- most notably with transfer speed.

USB 2.0 is an old standard, and if you&#;re doing anything but making infrequent small file transfers, avoid it -- its max transfer speed only reaches 480Mbps. The port is typically not color-coded on PCs.

USB connections beyond 2.0 can get somewhat confusing. You may see specifications listed as USB 3.0, USB 3.1 Gen1, or USB 3.2 Gen1. All three are essentially the same, providing speeds of up to 5Gbps and typically color-coded blue. Meanwhile, USB 3.1 Gen2 and USB 3.2 Gen2 also are the same, color-coded in red, and offer 10Gbps transfers.

The fastest, USB 3.2, or 3.2 2×2, offers up to 20Gbps.

USB-A is the most common (read: old school) connector type, featuring a rectangular box and a this-side-up-only connection. USB-C is newer, smaller, and more rounded, offering a reversible connector. Piggybacking this port is the DisplayPort protocol for video output. Some connectors use the USB-C port type but operate the Thunderbolt 3 or Thunderbolt 4 protocol with up to 40Gbps in transfer speed.

Some older devices use alternative connectors like eSATA and Firewire, but due to their reduced relevance, they should be avoided.

For the fastest possible external drive transfer speeds, you need a Thunderbolt NVMe SSD, like the Samsung X5.

Portability and durability

If you simply want an external drive for backups stored in your home, network-attached storage (NAS) devices may be a better bet. They typically sit as a stand-alone wired device on your local network, packing multiple drives and storage modes. Promise Technology, QNAP, and Synology are just three manufacturers that specialize in NAS devices.

However, if you want to keep your drive on you when out and about, portability is essential. It needs to be lightweight and small, so you can stuff it in a pocket or bag to access it immediately and quickly. Ideally, you want one that doesn&#;t require an external power cable, too.

Most external drives are far from weighty, and some are tiny, like the Samsung T5, offering huge digital storage capacity while being physically diminutive. On the other hand, SSDs tend to be a little smaller than their hard drive counterparts because they&#;re not housing stacked magnetic discs.

Another reason to consider an SSD over an HDD is durability. While modern-day external drives often come equipped with rugged casings to protect them against damage, the two technologies have very different physical makeups. With no moving parts, an SSD is more resistant to drop damage than a traditional hard drive and as a result is considerably more durable.

For a drive that's really durable, consider something like the Lacie Rugged.

Security

If the data stored on your external drive is sensitive in any way, encryption is a good idea. Many drives are compatible with software encryption solutions, and those are fine for most people.

For those who take their data security more seriously, you want to find a drive with hardware encryption. If you&#;re extremely safety conscious, you could even opt for a physical security system like the pin-code input on the Apricorn Aegis Padlock drive.

Some drives ship with strong casings to prevent physical tampering. While Kingston&#;s Ironkey flash drives don&#;t offer the same storage capacity as full-scale drives, they have a secondary security layer embedded in the printed circuit board (PCB), dipped in resin. This design makes it hard for anyone to physically access the memory chips inside the drive.

Compatibility

Out of the box, external hard drives are regularly formatted for a specific operating system. For example, an external drive formatted for Windows 10 may have problems working with MacOS, and vice versa. Some hard drives are formatted specifically for Linux, too.

This setup isn&#;t irreversible, however. You can reformat a hard drive or partition it to have different capabilities. But if you want to avoid the hassle, make sure the external drive is compatible with the target operating system.

Gaming

Want an external drive for on-the-go gaming or to augment a console&#;s storage? Your needs may be slightly different from the average user.

Here SSD speed is even more critical, as a slower drive can increase waiting times and game responsiveness. Xbox Series X and S owners can utilize the Seagate Expansion Card, to emulate its fast internal storage. Other external SSDs can be used for older Xbox One and Xbox 360 games, but not Xbox Series S/X games.

You only can play Sony PlayStation 5 games on its internal SSD for now, though you can play PS4 games on an external SSD or HDD. They load far faster on an SSD, so it&#;s worth using one over the PS5&#;s faster USB-C connection, if possible.

Some models, like the Silicon Power Armor A60 drive, also have built-in storage for cables and military-grade protection, which are nice extras if you take your data with you on the go.

Extra features

Despite having covered all the bases on your product research, you&#;ll also want to consider any extra features before making your purchase.

One feature you&#;ll want to look for is an extended warranty. This can help cover the cost of a new drive if this one fails, and some companies, like Seagate, have packages to help you recover your data for a reduced fee.

You also should take note of the kinds of cables that accompany your drive. Some newer phones and laptops use USB-C or Thunderbolt 3 connections, but the drive you want might include a USB-A cable. If that&#;s the case, you can still purchase that drive, but you&#;ll also have to buy a different cable or an adapter, which will add to your overall cost.

It&#;s also worth checking out newer drives that have cutting-edge features such as USB cable charging capacity and the ability to connect to Wi-Fi.

Despite the popularity of slim, speedy external SSDs, external hard drives&#;based on spinning platter disks&#;are still essential, cost-effective storage. Modern hard drives are ever more capacious for the money: For as little as $50, you can add a terabyte to your laptop or desktop by plugging in a USB cable. Important factors we consider in evaluating external hard drives include speed, capacity, and cost per gigabyte, as well as physical size, style, ruggedness, and the interface it uses. This guide makes sense of these and many more factors. PCMag has been testing and reviewing external drives for decades, and we've outlined here our top choices. Our current pick for the best external desktop drive for most people is the WD My Book, and for portable drives, the WD My Passport, Works with USB-C (6TB), though we stand behind all our recommendations. Read on for all of them, plus the shopping basics to know.

Deeper Dive: Our Top Tested Picks

Best Desktop Hard Drive for Most People

Western Digital My Book

4.5 Outstanding

• Comes in a variety of large capacities.

• Three-year warranty.

• Requires external power adapter.

If you're addicted to downloading videos and snapping up every game you can find online, chances are you need inexpensive, voluminous storage to house it all. The Western Digital My Book, now available in capacities up to a whopping 22TB, can hold thousands of hours of video, or millions of MP3s or photos. With a good mix of capacity, pricing, and performance, it's a shoo-in as an Editors' Choice pick for desktop external hard drives.

Most of us need a large repository for our data files, including the scads of pictures we've taken over the years, music files, and those downloaded movies we've been meaning to watch. The Western Digital My Book is an excellent choice to store them all, offering tremendous capacities at a low cost per gigabyte..

Drive Type

External Desktop

System-Side Interface

USB 3.0

USB Powered?

Capacity

8 TB

Spin Rate

rpm

Cables Included

USB Micro-B-to-A

Backup Software Included?

Warranty (Parts/Labor)

3 year(s)

Other Features

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$159.63 Amazon

$179.99 B&H Photo Video

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Western Digital My Book Review

Best Portable Hard Drive for Most People

WD My Passport, Works with USB-C (6TB)

4.0 Excellent

• 6TB is current peak capacity for a portable hard drive

• Includes Acronis True Image backup software

• 256-bit AES encryption

• Good benchmark results for a portable platter-based drive

• USB-C compatibility requires included adapter

• Platter drives are inherently slow compared with external SSDs

The WD My Passport, Works with USB-C is now available at the highest capacity (6TB) of any pocketable, spinning hard drive on the market today. Despite its name, it connects via a USB Micro-B port&#;its included cable is a USB Micro-B-to-USB-A, plus an A-to-C dongle for connecting to a computer's USB-C port. Its speeds on our benchmarks were actually a little faster than the similar 6TB WD My Passport Ultra with its native USB-C port&#;though still far below portable SSD speeds&#;and it is priced a little lower.

Spinning hard drives survive in this age of superfast portable SSDs due to their low cost per gigabyte, and the 6TB WD My Passport, Works with USB-C lists at a minuscule 3.2 cents per gig while bringing the highest capacity now available in a portable hard drive. Acronis True Image backup software and 256-bit AES hardware-based encryption further sweeten the pot. This drive is a winner for users who seek high capacity and good value in a platter hard drive, and who appreciate built-in software and security features.

Drive Type

External Portable

System-Side Interface

USB 3.2

USB Powered?

Capacity

6 TB

Spin Rate

rpm

Cables Included

USB Micro-B-to-A, USB-A-to-C adapter

Backup Software Included?

Warranty (Parts/Labor)

3 year(s)

Other Features

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$84.99 Amazon

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WD My Passport, Works with USB-C (6TB) Review

Best Portable Hard Drive for Gamers

WD Black P10 Game Drive

4.0 Excellent

• Sturdy, compact design

• Good grippability

• Appealing gamer aesthetic

• USB Type-C cable not included

With the ribbed appearance of a corrugated shipping crate, the WD Black P10 Game Drive&#;s styling gives it the appearance of a container you (or your enemies) might use for cover in the wasteland of one of the games you might store on it. If you appreciate the gamer aesthetic, the P10 is an obvious choice over more vanilla offerings like the WD My Passport or the Seagate Backup Plus Ultra Touch.

That said, as a platter-based hard drive, it's best equipped to store a game library; you're better off loading the games you're currently playing from an SSD. If you conservatively figure an average game size of 100GB, the 4TB version tested here can hold about 40 titles, serving as the stylish main repository of your collection for years to come, and for a much more modest outlay than you'd spend on an SSD of similar capacity.

The WD Black P10 Game Drive is primarily for gamers to store a game library and who appreciate the edgy shipping-container aesthetic that's a common motif in post-apocalyptic FPS games (and a few such movies as well). It's also cost-effective compared with using an SSD to house your library.

Drive Type

External Portable

System-Side Interface

USB 3.0

USB Powered?

Capacity

4 TB

Spin Rate

rpm

Cables Included

USB Micro-B-to-A

Backup Software Included?

Warranty (Parts/Labor)

3 year(s)

Other Features

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$78.59 Amazon

$149.99 Best Buy

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WD Black P10 Game Drive Review

Best Desktop Hard Drive for Creative Pros

LaCie 2big RAID

4.0 Excellent

• Can use RAID 0 for higher speed and capacity, RAID 1 for drive mirroring, or JBOD (RAID off).

• Five-year warranty with five years of Data Rescue recovery.

• Drives are hot-swappable.

• High price per gigabyte.

• Need to download utilities to manage the drive.

• Kensington lock slot secures only the case, leaving the drives easily removable.

The LaCie 2big RAID external hard drive, aimed squarely at videographers, photographers, and other content creators, earns kudos for design excellence in both looks and features. The handsome gray and black case houses two spinning-platter drives&#;4TB each in the 8TB version we tested. You can configure the 2big so your computer sees it as two separate 4TB drives, as a single 8TB drive with faster performance, or as a 4TB drive that's automatically mirrored or backed up to the second. You can also hot-swap drives, easily sliding an old one out and a new one in with no tools, without turning the LaCie unit off.

The LaCie 2big RAID array promises the reliability and delivers the performance benefit you'd expect from 7,200rpm platters, magnified by the default RAID 0 setting, while the optional RAID 1 setting is available if you want data redundancy. (A JBOD mode is also available if you don't want to use RAID.)

The LaCie 2big RAID desktop array offers cavernous capacity to creative types and others who need to store and work with massive amounts of data. Available in capacities up to 16TB when we reviewed it, it has since added even higher volume, up to a monstrous 40TB.

Drive Type

External Desktop

System-Side Interface

Thunderbolt 3, USB 3.0

USB Powered?

Capacity

8 TB

Spin Rate

rpm

Cables Included

USB-C to USB-C, USB-C to USB-A

Backup Software Included?

Warranty (Parts/Labor)

5 year(s)

Other Features

Hot swappable drives

Link to coredrillpros.

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$754.21 Amazon

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LaCie 2big RAID Review

Best Rugged Portable Hard Drive for Windows Users

ADATA HD710M Pro External Hard Drive

4.0 Excellent

• Durable in drop tests.

• Good dollar-per-gigabyte ratio.

• Trim enclosure.

• Lightweight for a ruggedized unit.

• Cable storage around the edges.

• Camouflage exterior may not be for everyone.

• Plastic housing only.

There are rugged hard drives, and then there's the ADATA HD710M Pro External Hard Drive. Its IP (ingress protection) rating of IP68 for dust resistance and waterproofing (in the last case, submerged up to two meters for up to one hour) matches the best rating of any hard drive or SSD we have reviewed. The ADATA HD710M Pro also has grips and channels around the edges of the drive to keep the detachable USB cable tethered to the drive at all times, even when not plugged into the USB connector.

The ADATA HD710M Pro is a good choice for outdoor workers, as the drive is able to take a tumble, and keep out water, sand, and dust. It comes in at a better cost per gigabyte than its solid-state brethren as well.

Drive Type

External Portable

System-Side Interface

USB 3.0

USB Powered?

Capacity

2 TB

Spin Rate

rpm

Cables Included

USB Micro-B-to-A

Backup Software Included?

Warranty (Parts/Labor)

3 year(s)

Other Features

GET IT NOW

$74.98 Amazon

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ADATA HD710M Pro External Hard Drive Review

Best Rugged Portable Hard Drive for Mac Users

SanDisk Professional G-Drive ArmorATD

4.0 Excellent

• Rugged enough to protect from the elements, with rubberized sheath and port cover

• Attractive design

• Ideal for use with macOS

• Both USB-C and USB-A cables bundled

• Competitive pricing

• Lacks software suite and hardware-based encryption

• Requires reformatting for use with Windows

The SanDisk Professional G-Drive ArmorATD is a cost-effective, semi-rugged external hard drive available in capacities up to 5TB. As a spinning (5,400rpm) platter drive, its speed can't compare with an SSD, but it should work well for travelers or mobile workers who need lots of capacity for the spend. With a rubber bumper and internal shock mounts, the ArmorATD is rated to survive up to 1,000 pounds of pressure or a drop from 3.3 feet. Its ingress protection (IP) rating of IP54 promises some security against sand and rain. It comes formatted in Mac-friendly HFS+, one of two formats (along with APFS) compatible with the macOS Time Machine backup system. If you only have a Windows computer, you could (carefully) reformat it to NTFS, but you would probably be better off getting a hard drive already formatted in NTFS or exFAT.

Like other products in the SanDisk Professional line, the G-Drive ArmorATD is strongly geared to Mac use. It's best for traveling Mac users looking for a drive that can withstand a tumble or a rainstorm and want better capacity for the price than they would get with an SSD.

Drive Type

External Portable

System-Side Interface

USB 3.0

USB Powered?

Capacity

2 TB

Spin Rate

rpm

Cables Included

USB-C to USB-C, USB-C to USB-A

Backup Software Included?

Warranty (Parts/Labor)

3 year(s)

Other Features

GET IT NOW

$84.99 Amazon

$89.99 B&H Photo Video

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SanDisk Professional G-Drive ArmorATD Review

Best Security-Minded Desktop Hard Drive

iStorage DiskAshur DT2

4.0 Excellent

• Immense capacity

• Low cost per gigabyte for a security-centric drive

• AES-XTS 256-bit full-disk hardware encryption

• FIPS 140-2 Level 2/3, NCSC CPA, NLNCSA BSPA, and NATO Restricted certifications

• Easy for authorized users to unlock

• No protective case or ruggedness features

• Low score in PCMark 10 benchmark for everyday storage tasks

With cavernous capacity and a minuscule cost per gigabyte compared with security-centric SSDs, the iStorage DiskAshur DT2&#;a desktop-style hard drive&#;is a formidable solution for corporations, institutions, and agencies needing to keep sensitive data safe. With a slew of protective features and boasting an impressive set of certifications, this PIN-authenticated external drive is easy for authorized users to access but impervious to attempts by outsiders to break in. As a desktop hard drive, it is not USB-powered, but instead must be plugged into its included AC adapter. As it will generally be used in an office or server room setting, it lacks any ruggedness features to speak of&#;the protection it offers is from human threats.

The DT2 isn't slim or portable like many external drives&#;in form, it&#;s a classic desktop spinning hard drive. But it is easy for authorized users to unlock and access using its built-in keypad, and it has a slew of security features and certifications to assure you it'll keep bad guys out. If you need to store and protect large volumes of data, this is a great choice.

Drive Type

External Portable

System-Side Interface

USB 3.2

USB Powered?

Capacity

14 TB

Spin Rate

rpm

Cables Included

USB-B to USB-A

Backup Software Included?

Warranty (Parts/Labor)

3 year(s)

Other Features

GET IT NOW

$194.00 Amazon

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iStorage DiskAshur DT2 Review

Best-Designed Portable Hard Drive

LaCie Mobile Drive ()

3.5 Good

• Sleek design

• Available in capacities up to 5TB

• LaCie Toolkit software handles backup, restore, and mirroring

• Three-year access to data recovery service

• Compatible with Windows, Macs, and iPads

• Relatively pricey

• Low PCMark 10 overall test score

Sporting a tasteful silver-and-black chassis, the LaCie Mobile Drive () is a mildly redesigned version of the company's external hard drive that we reviewed in March . Available in capacities up to 5TB, the new drive is easy to set up and use. Its LaCie Toolkit software enables backup, restore, and mirroring. Its touch of style brings a slightly higher cost than other external spinning hard drives, however.

The iteration of the LaCie Mobile Drive is a good choice for anyone who values capacity over speed, and who appreciates a rare touch of elegance in a platter-based hard drive. It costs a tad more per gigabyte than much of its platter-based ilk, but less than SSDs of equivalent capacity.

Drive Type

External Portable

System-Side Interface

USB 3.2

USB Powered?

Capacity

5 TB

Spin Rate

rpm

Cables Included

USB-C to USB-C

Backup Software Included?

Warranty (Parts/Labor)

3 year(s)

Other Features

GET IT NOW

$164.29 Amazon

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LaCie Mobile Drive () Review

Buying Guide: The Best External Hard Drives for

How to Choose an External Hard Drive

Hard drives may get you more capacity for your dollar by far, but first you need to consider a major difference in external storage these days: the hard drive versus the SSD. Solid-state drives (SSDs) have fewer moving parts than traditional hard drives, and they offer the speediest access to your data. Unlike a conventional disk-based hard drive, which stores data on a spinning platter or platters accessed by a moving magnetic head, an SSD uses a collection of flash cells&#;similar to the ones that make up a computer's RAM&#;to save data.

Just how much faster is it to access data stored in flash cells? Typical read and write speeds for consumer drives with spinning platters are in the 100MBps to 200MBps range, depending on platter densities and whether they spin at 5,400rpm (more common) or 7,200rpm (less common). External SSDs offer at least twice that speed and now, often much more, with typical results on our benchmark tests in excess of 400MBps for the slowest ones. Practically speaking, this means you can move gigabytes of data (say, a 4GB feature-length film, or a year's worth of family photos) to an external SSD in seconds rather than the minutes it would take with an external spinning drive.

Not only is it faster to read and write data stored in flash cells, but it's also safer. Because there is no spinning platter or moving magnetic head, if you bump the SSD while you're accessing its data, there is no risk that your files will become corrupted and unreadable.

(Credit: Molly Flores)

Still, while external SSDs are cheaper than they were a few years ago (see the best we've tested at the preceding link), they're far from a complete replacement for spinning drives. Larger external drives designed to stay on your desk or in a server closet still almost exclusively use spinning-drive mechanisms, taking advantage of platter drives' much higher capacities and much lower prices compared with SSDs.

Portable hard drives can be a great value if what you need is raw capacity above all else. You can find a 2TB portable hard drive for less than $100 with ease (possibly even a 4TB one, depending on the day), while 5TB hard drives go for about $150 and 6TB models for about $180. A 2TB SSD, though? Expect to pay around twice as much as you would for that 2TB hard drive. Likewise, most 4TB external SSDs start around $300, and most 8TB models start at $600 and up.

Should I Get a Desktop Hard Drive, or a Portable Hard Drive?

If you have a large media-file collection&#;perhaps you are a photo or video editor, or maybe a movie buff&#;you'll likely need several terabytes of space in which to store it. In that case, your best option is a desktop-class hard drive. We define these as having one or more spinning-platter drives inside and requiring a dedicated power cable plugged into AC power to work. (Of course, in this scenario, your files are going to have to stay at your desk.)

(Credit: Molly Flores)

A desktop drive with a single platter mechanism will typically use a 3.5-inch drive inside and comes in capacities up to around 20TB. Most are roughly 5 inches tall and 2 inches wide. In addition to storing large media collections, these drives can also serve as inexpensive repositories for backups of your computer's hard drive that you schedule, using either software that comes with the drive or a third-party backup utility.

The next size up for consumer desktop drives is about the same height but twice as wide, to accommodate more than one platter-based hard drive mechanism in the chassis. These larger models are more expensive but also much more capacious&#;think 24TB or more (in that case, populated by two 12TB drive mechanisms). In the case of these and single-platter-drive products, you're not meant to swap out the drive or drives inside.

(Credit: Zlata Ivleva)

The largest desktop drives are often much, much bulkier than the first two categories, so big that you'll want to stick them under your desk or in a dedicated server closet. They're mostly intended for professional use in editing studios, surveillance control rooms, and the like. Their defining characteristic is the ability to swap drives in and out of their multi-bay chassis easily, so most provide quick access to the drive bays at the front of the device.

Most such multi-bay devices are sold without the actual hard drives included, so you can install any drive you want (usually, 3.5-inch drives, but some support laptop-style 2.5-inchers). Their total storage capacities are limited only by their number of available bays and the capacities of the drives you put in them. Some in the storage industry refer to these (as well as smaller-capacity externals as a whole) as DAS&#;for "direct attached storage"&#;to distinguish them from NAS, or network attached storage, many of which are also multi-bay devices that can take two or more drives that you supply. (See our separate roundup of the best NAS drives.)

At the other end of the physical-size spectrum are portable drives. Hard drive-based portables make use inside of the same kinds of platter-drive mechanisms used in laptops. These are called generically "2.5-inch drives," though they are actually a smidge wider than that. Any portable platter-based hard drive should fit easily in a purse or even a coat pocket. As a rule, portable drives get their power from the computer to which you connect them, through the interface cable, so there's no need for a wall outlet or a power cord/brick.

(Credit: Zlata Ivleva)

The best way to gauge relative value among similar portable drives is to calculate the cost per gigabyte, dividing the cost of the drive in dollars by the capacity in gigabytes to see the relative per-gig price. Example: A $60 1TB (1,000GB) hard drive would run you about 6 cents per gigabyte, while an $80 2TB (2,000GB) drive would work out to about 4 cents per gigabyte.

Need Redundancy or Extreme Speed? Consider a RAID-Enabled Drive

If you buy a larger desktop drive with two or more discrete spinning-platter drive mechanisms inside, you'll almost certainly have the option to configure the drive as a RAID array using included software. Depending on which RAID level you choose, you can prioritize capacity, speed, or data redundancy, or some combination thereof.

(Credit: Zlata Ivleva)

A collection of spinning drives configured with a RAID level designed for faster data access can approximate the speeds of a basic SSD, while you should consider a drive with support for RAID levels 1, 5, or 10 if you're storing really important data that you can't afford to lose. Hit the link above for an explanation of the traits and strengths of each RAID level. Some require you to sacrifice raw capacity for data redundancy, so you'll want to pay attention to the nuances of each level.

Which Drive Interface Should I Get?

How an external drive connects to your PC or Mac is second only to the type of storage mechanism it uses in determining how fast you'll be able to access data. These connection types are ever in flux, but these days, most external hard drives use a flavor of USB, or in rare cases, Thunderbolt. 

Right now, the fastest connection type in wide use on hard drives is Thunderbolt 3, which is handy assuming you have a newer laptop or desktop with a Thunderbolt 3 port. (Thunderbolt 4 is found on most new Macs and some new PCs, but hard drives that use it are not yet common.) Both Thunderbolt interfaces piggyback on a USB Type-C connector (not all USB Type-C ports support Thunderbolt, though) and offer blazing peak throughput of up to 40GBps. As a bonus, a desktop drive that supports Thunderbolt might also come with additional DisplayPort and USB connections that allow you to use the drive box as a hub for your keyboard, mouse, monitor, and other peripherals. (See our explainer Thunderbolt vs. USB-C: What's the Difference?)

You'll only see the speed benefits of Thunderbolt, however, if you have a drive that's SSD-based, or a multi-drive, platter-based desktop DAS that is set up in a RAID array. For ordinary external hard drives, Thunderbolt is very much the exception, not the rule. It tends to show up mainly in products geared toward the Mac market.

A desktop hard drive with a single platter-based mechanism inside, or a portable hard drive, is far more likely to make use of plain old USB instead. Almost every recent drive we have reviewed supports USB, and the same goes for laptops and desktops. USB ports are ubiquitous, and many external drives now come with cables with both rectangular USB Type-A connectors and oval USB Type-C ones to enable adapter-free connections to PCs that have only one type. If the drive includes only a single cable, you may need an adapter, depending on your computer's available USB ports. Be mindful of that.

(Credit: Zlata Ivleva)

In addition to their physical shape differences, USB ports on the computer side will variously support USB 3.0, 3.1, or 3.2, depending on the age of the computer and how up to date its marketing materials are. You don't have to worry about the differences among these three USB specs when looking at ordinary hard drives, though. All are inter-compatible, and you won't see a speed bump from one versus the other in the hard drive world. The drive platters' own speed is the limiter, not the flavor of USB 3.

The only case with hard drives where the USB standard matters much is if you connect a drive to an old-style, low-bandwidth USB 2.0 port, which is better reserved for items like keyboards and mice. (Also, if it's a portable drive, that USB 2.0 port may not supply sufficient power to run the drive in the first place, so the speed shortfall may be moot.) Any remotely recent computer will have some faster USB 3-class ports, though.

Is a Rugged or Secure Hard Drive Worth It?

If you carry your drive around frequently, you'll want to pay attention to how rugged the drive is. Some models include plastic bumpers, and some even meet military standards for shock and dust protection. (Look for support for specifications such as IP67 or IP68.)

A subset of drives come with essentially uncrackable AES 256-bit hardware-based encryption that you can engage. A few are endowed with a host of additional security features, anything from encasing the drive's innards in epoxy (to destroy the electronics, should the drive's casing be physically breached) to sporting a virtual keypad whose letters and numbers change location each time the drive is connected, to prevent an onlooker from guessing, say, a password from a user's sequence of keystrokes. Many such drives are designed to meet rigorous certification standards mandated by some corporations and government agencies. You pay a premium for a secure hard drive, but with one you can rest assured that your data won't be stolen.

(Credit: Zlata Ivleva)

Perhaps the only thing you don't need to pay all that much attention to is the warranty. Sounds counter-intuitive, perhaps? Sure, a long warranty is nice. But if your drive breaks because you dropped it, the warranty likely won't cover that, anyway. Even if the drive fails because of a manufacturing defect, most warranties simply replace the drive and don't cover the cost of recovery services that attempt to rescue your data from the broken drive. For most folks, the real value lies in what's on your drive, not the drive itself.

Ready to Buy the Right External Hard Drive?

We trust our advice helped clarify what you need to know. To get you started in the right direction on product picks, the external hard drives (platter-based models) listed here are the best we've tested of late, at a variety of prices and capacities. They're a fine starter mix for your research. Remember that most of them come in a range of capacity options, so know that even if the specific model we tested is too big or small for your needs, the drive maker may offer it in a more fitting size. And don't forget to explore our recommendations for the best external SSDs as well if you need more speed than a platter-based drive can offer.

If you want to learn more, please visit our website Hdd Tooling.