The Best External SSDs for 2025

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Need to expand the local storage on your PC or Mac for music and movies, or all those pics and videos that collect on your phone? An external solid-state drive (SSD) is a fast and convenient fix. PCMag has been testing and reviewing SSDs since the very first models debuted, subjecting internal and external drives to our rigorous benchmark testing. Important factors we consider in evaluating them include speed, capacity, and cost per gigabyte, as well as physical size, style, ruggedness, security features, and interface. This guide makes sense of these and many more factors. The Crucial X9 Pro is our current overall top pick for most buyers, but we stand behind all our recommendations, selected for specific use cases and budgets. See them all below, then read on for a detailed guide to shopping for the drive that best meets your needs.

As you can see above, there's a wide variety of portable SSDs to pick from. As you shop, you'll need to pay attention to capacity, size and weight, and a drive's interface or connection to your PC, as well as whether you need one with a rugged casing.

First: Here's why you want an SSD versus a hard drive. Unlike a hard drive, which stores data on those spinning platters accessed by a moving magnetic head, a solid-state drive uses a collection of "persistent" flash-memory cells to save data. These are similar to the silicon that makes up a computer's RAM, but they retain your data when electrical power is cut off.

Since hard drives are mechanical devices that use mature technology, you can get relatively large amounts of storage capacity for the money. But the same tech that makes hard drives a tantalizing value becomes their most significant liability when used on the go. If you drop the drive, you could damage the interior mechanism and make your data inaccessible. By contrast, if you jolt an SSD while you're reading or writing data, there is no risk that your files will become corrupted and unreadable.

Is an External SSD Faster Than an External Hard Drive?

Yes: Again, hard drives are slower because they have to physically rotate disks and move a reader arm to access your data. How much faster is it to read data from flash cells than from particular points on spinning platters? Typical throughput for consumer hard drives is 100MBps to 200MBps, while SSDs that support Thunderbolt 3 or 4, or USB 3.2 Gen 2x2, can have read and write speeds pushing 2,000MBps or even higher. (One factor in hard drive speed is spin rate—among external drives, 5,400rpm units are more common and more affordable than 7,200rpm.)

Our typical benchmark-test results for even run-of-the-mill external SSDs show speeds over 400MBps. Practically speaking, this means you can move gigabytes of data (say, a 4GB feature film or a year's worth of family photos) to your external SSD in seconds rather than the minutes it would take with an external hard drive.

Still, you do pay a bit more for that speed and durability. Want a 2TB portable hard drive? You can find one from major brands such as Seagate and Western Digital for as little as $60. A 2TB external SSD, on the other hand, will generally run you from about $80 to $15. If speed, resilience, and portability are critical to you, spending the extra money is probably worth it. If they're not, proceed with care. When considering whether to buy an external SSD, make sure you know what you're paying a premium for.

External SSDs are now readily available and cheaper than a few years ago, but it will probably be a while before they are a complete replacement for hard drives. Physically larger external drives designed to stay on your desk or in a server closet still mostly use 3.5-inch platter drives inside. They take advantage of their vast capacities and much lower prices per gigabyte than SSDs.

What Is the Best External SSD Interface?

External solid-state drives are, essentially, internal SSDs (the same kind that power laptops or live inside desktops) with an outer shell and some bridging electronics. As a result, external drives use one of two internal "bus types" that, in part, dictate their peak speed: Serial ATA (SATA), or PCI Express (PCIe). The latter is usually associated with Non-Volatile Memory Express (NVMe), a protocol optimized for SSDs that speeds up data transfers.

SATA-based drives tend to be a little cheaper; they're also slower, but just fine for most users' everyday applications. SATA-based SSDs typically top out at around 500MBps for peak read and write speeds, just a bit below the ceiling of the USB 3.0 interface. (Much more about that in a moment.) However, if you're transferring large files such as videos often, you may want to spring for a PCIe/NVMe-based external SSD. That also ties in with the port you'll plug your SSD into.

Sellers of portable SSDs seldom indicate if the drive is SATA- or PCIe-based. However, checking the specs can be a dead giveaway. If the drive tops out at sequential read and write speeds between 400MBps and 550MBps, it's very likely SATA-based. Speeds of 800MBps or higher indicate a PCIe-based drive.

What Is the Right Kind of USB for Your External SSD?

Arguably more important than the type of storage mechanism inside an external SSD is how it connects to your PC or Mac. Almost all external SSDs today plug into either some flavor of USB port or a Thunderbolt port.

There are enough different flavors of USB to make your head spin, but thanks to a combination of renaming (for example, USB 3.1 has become USB 3.2) and obsolescence, it has been somewhat simplified. Recent external SSDs have USB interfaces that fall into three types: USB 3.2 Gen 2, with a maximum throughput of 10Gbps; USB 3.2 Gen 2x2, aka "SuperSpeed USB," which supports speeds up to 20Gbps; and USB4, which itself has two different flavors, both called SuperSpeed USB, one with a maximum throughput of 40Gbps and the other, 20Gbps. (For USB4 SSDs, often the drive's port will be labeled with text and/or icon to identify the version.)

USB 3.2 Gen 2, with speeds up to 10Gbps, is supported by nearly all recent laptops, and the majority of USB 3.2 ports are Gen 2. All of these versions of USB are backward-compatible with earlier versions; performance will just bounce down to the slower of the two (the drive's supported spec, or that of the system-side port).

You won't see nearly as many USB 3.2 Gen 2x2-capable ports on PCs. In spite of this, a surprising number of Gen 2x2 SSDs are hitting the market. While there are both USB-A and USB-C connectors for USB 3.2 Gen 2, Gen 2x2 ports are exclusively USB-C. Desktop-PC expansion cards specifically supporting USB 3.2 Gen 2x2 are available through retailers for less than $50. Expect that spec to be supplanted by USB4 and Thunderbolt 4 as the 2020s move on.

The first USB4 external SSDs were introduced in late 2023, with theoretical maximum throughput speeds of up to 40Gbps. However, as mentioned, there are two different USB4 flavors; one can only muster speeds up to 20Gbps. Be sure to read the specs of any USB4 device you're buying to be sure it's the type you want; throughput speeds will also be marked on a label next to the device's ports.

And to make matters even more complicated, you'll still see older USB terminology on many products, so you need to know what term correlates to what. Some older PCs (and even some current desktops) have USB 2.0 ports, but you want to avoid using them with portable drives. This standard's theoretical bandwidth of 60 megabytes per second (60MBps) is a bottleneck even for a platter drive. A USB 3.0 computer port, which offers a theoretical peak bandwidth of 640MBps (or 5Gbps), is a step up, but is still slow for most current external SSDs. Until about five years ago, most SSDs' real-world transfer speeds topped out somewhere in the range of 450MBps or below, so these ports were fine back then. Finally, the deprecated USB 3.1 standard supports data transfer speeds of up to either 5Gbps or 10Gbps, and the speed is frequently specified next to the port in words or with an icon.

Really, all this calls for a little chart of the current USB standards to keep them straight...

As you can see, some USB specs are tied to specific system-side physical USB connectors. We'll get into that in a moment.

Can I Use Thunderbolt for an External SSD?

Thunderbolt is the least common external SSD interface, and drives that use it are often geared toward Mac users since macOS laptops were quicker than their Windows rivals to move to Thunderbolt. You'll find it on resolutely speed-focused drives and specialized desktop-style drives that may contain multiple SSDs in a RAID format.

Most workaday SSDs don't come close to saturating this interface, so there's no point in paying a premium for a Thunderbolt drive unless you specifically need the port and the speed because of your computer. You can plug a USB-C drive into a Thunderbolt port, so you're not obliged to buy a Thunderbolt drive if you don't need the speed but have the port.

Computers equipped with a Thunderbolt 4 port—currently the most common variant—offer a blazing top bandwidth of 40Gbps. These ports are found on Macs and a growing number of mainstream-to-high-end Windows laptops. The physical connector is the same as USB-C, but Thunderbolt SSDs are not backward-compatible with USB Type-C ports that lack Thunderbolt support; look for the little lightning-bolt symbol next to the port.

A few very new PCs support the latest Thunderbolt 5 standard, which doubles the theoretical throughput maximum to 80Gbps. Both OWC and Sabrent are launching Thunderbolt 5 external SSDs with top speeds in excess of 6,000MBps. Thunderbolt 5 is backward-compatible with Thunderbolt 3 and 4 as well as USB4.

The Physical USB Port: USB Type-A vs. Type-C, and More

Have you got interface fatigue yet? Alas, that's not the last thing to consider around USB and Thunderbolt!

These days, system-side physical USB ports take the form of USB Type-A (the familiar, older rectangular kind) and USB Type-C (smaller and roughly oval). The physical type is not necessarily an indicator of which specific USB transfer-rate spec the port supports, but you need to make sure you can plug in what you get.

Many SSDs come with cables for both kinds (Type-A and Type-C) at the computer end, or one cable plus an adapter. Two full cables are generally best, as adapters can be awkward and easy to lose. You'll want to match what comes in the box with the ports your PC has (and has free). Also, match specs; spending extra, for example, for a 10Gbps USB 3.2 Gen 2 SSD if you only have 5Gbps-capable ports may be pointless.

Also, Don't confuse the system-side interface with the connector that joins the cable to the drive itself. On most newer portable SSDs, the connector at the SSD end is a USB Type-C port (the same as the kind you might find system-side)...

On others, though, the connector might be a Micro-USB Type-B, a flat, wide connector different from any USB port you'll see on a laptop or desktop.

Is a Rugged External SSD Worth It?

Indeed, if you carry your drive around frequently, you'll at least 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 Ingress Protection (IP) ratings such as IP68, explained at the previous link.

And, of course, if you're carrying your drive around, you want it to look nice. Some come in multiple colors, while most are small and slim enough to be tucked into a shirt pocket.

Perhaps the only thing you don't need to weigh too heavily is the warranty. If your drive breaks because you damaged it, the warranty likely won't cover it. 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 device. A long warranty is well and good, but the real value in a drive usually lies in what you have on it.

This is also where a spec known as the "terabytes written" rating (or TBW) comes in. It refers to how much data can be written to a drive over its life before some cells begin to fail. The entire drive won't stop functioning; rather, less and less storage will be made available as time goes on.

How to Tell What Is the Best External SSD?

Here are three key things to look out for when shopping for an external SSD:

COST PER GIGABYTE. The way to calculate relative value on drives like these is to perform some simple math and figure the cost per gigabyte based on the price of a given drive on the day you're shopping. Because SSD pricing fluctuates all the time, relative value does, too.

Generally, the higher a drive's capacity, the cheaper it will be per gigabyte. But that's not always true; sometimes the highest-capacity drives come at a per-gigabyte price premium. The basement for budget external SSDs is currently about 7 cents per gigabyte, mostly from second- or third-tier vendors. Calculate your bottom-line price when comparing a host of drives.

RUGGEDIZATION. The degree of ruggedness varies from drive to drive, and we mention in our reviews factors such as whether an SSD is shock- and crush-proof, and to what degree. Also, we note whether a drive has an ingress protection (IP) rating, denoting its resistance to dust, dirt, and water. An IP67 or IP68 certification is a good spec to look for if you're serious about waterproof and dustproof drives.

Some models, though, like a few from Apricorn's Fortress series, combine major ruggedness with physical and electrical security; it's almost impossible to crack open those drives to get at the components and chips inside without destroying them.

CARRY WEIGHT. Most SSDs weigh a negligible couple of ounces. The carabiner retention loop of SanDisk's Extreme family of external SSDs is especially handy, because many SSDs are small and light enough that losing them is an easy and expensive mistake.

Can You Put an SSD in an External Enclosure?

If none of the drives we've selected for this roundup sounds appealing to you (or you already own an extra internal SSD), there's one more option available: SSD enclosures. These are plastic or metal housings into which you can put your own SATA 2.5-inch or M.2 solid-state drive to take with you.

Enclosures come in 2.5-inch form factors (into which you would put a 2.5-inch SATA SSD) or M.2 ones. The stick-style M.2 SSD is much smaller and lighter, but know that M.2 drives themselves come in both SATA and PCIe bus flavors. You need to be sure your enclosure supports the bus type of M.2 drive you're putting in it.

Also, just because you put a PCIe NVMe drive in an enclosure doesn't mean you should magically expect it to go any faster than a standard external SSD. Any drive placed in an enclosure is still subject to the peak USB speed supported by the enclosure's own electronics and controller, and by the USB protocol supported by the port you plug it into.

Though there are exceptions, most enclosures are not as durable or rugged as major-maker portable SSDs are. This can be a drawback for those who take their SSDs into dangerous environments (think wildlife photographers or first responders), so be sure that you know what your drive will be exposed to before you go this route. Your data could be at greater risk for corruption than in an SSD purpose-built to withstand the elements.

Ready to Buy the Right External SSD for You?

We trust that you're better armed now for buying an SSD than ever! Our picks for the best external SSDs vary widely in features and price, but all should deliver plenty of speed and peace of mind, if that's what you seek from your portable storage. Our summary of top drive choices above and our spec comparison chart should bubble up at least one perfect model for you and your budget.

Don't need (or don't want to spring for) an SSD? Then check out our roundup of the best external hard drives. And if you're building a desktop or upgrading a desktop or laptop, read about how to buy the best M.2 SSDs, as well as the best SSDs for upgrading your laptop.