How to choose an external hard drive

While cloud storage is convenient, it’s not guaranteed to be at your fingertips forever. Eventually, we’ll move on from cloud storage to something we have yet to imagine. Until then, backing up your files to an external drive is just good practice.

Why create a backup? To ensure that all your vital information is safe and secure, no matter what happens to your computer or internet connection. Send everything to an external drive and use the cloud as a secondary source.

But with tons of options now available, where do you start? Read on to find out how to choose an external drive for better peace of mind.

Storage capacity

Samsung T5 SSD review

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

What size, then, is best? That depends on you.

If you want a device that’s good for simply transferring documents, photos, or other media from one device to the other, or just want to expand the storage space of your low-end laptop or tablet, then a mid-range flash drive may be ideal.

While the largest of those can stretch up to 2TB of storage space, they get very expensive and are unnecessarily big for simple transfers. Instead, save your money and buy a drive with 64GB, which can cost less than $20. You can get drives with double the size for not much more.

If you’re interested in storing a lot more or keeping files and folders long term, you’ll want something bigger. A 1TB drive should suit most needs for the foreseeable future, but if you envision storing hundreds of movies — maybe you ripped your DVD collection — or just never want to run out of space, there are drives available today that offer multiple terabytes of space.

For instance, the Seagate Backup Plus is available from 1TB to 5TB in capacity. The 1TB model is not much more than $90 while the 5TB model hits $160.

SSD vs. HDD

External drives are served up in two flavors: HDDs and SSDs. We talk more in-depth about the differences between the two in a separate article and below where it affects specs, but essentially they are two different ways of storing and accessing data.

HDDs (hard drive disk) use spinning magnetic disks to store data. Read/write heads change this data as necessary, which is why 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.

Broadly speaking, SSDs are significantly faster than HDDs but can grow very expensive. HDDs are cheaper, but also larger, slower, and more easily damaged. For external drives, it’s usually best to choose an SSD except in particular circumstances.

Transfer speed

macbook usb type c
Maurizio Pesce/Flickr

Size isn’t everything, even when it comes to external drives. Transfer speed is incredibly important too because if you transfer files back and forth to a huge 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 connector between your external drive and your PC or mobile device, there are several common options to consider. Most drives today use a USB interface, but several generations have some distinct differences — most notably with transfer speed.

USB 2.0 is an old standard and should be avoided if you’re doing anything but making infrequent small file transfers, as it 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 are also the same, color-coded in red and serving up 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 and. Some connectors use the USB-C port type, but operate the Thunderbolt 3 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.

That all said, you want a Thunderbolt 3 connection first. If it’s too expensive or your device doesn’t have a USB-C port (or Thunderbolt 3), look for USB 3.1/3.2 Gen 2 support next or move down the line.

Portability and durability

LaCie Rugged Type-C
Bill Roberson/Digital Trends

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 important. 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. In the inverse of storage space, 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 durable to drop damage than a traditional hard drive.

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 security 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) which is dipped in resin. This design makes it hard for anyone to physically access the memory chips mounted inside.

Compatibility

Out of the box, external hard drives are often formatted for a specific operating system. For instance, 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 than the average user.

Here SSD speed is even more important, as a slower drive can affect waiting times and game responsiveness. USB 3.1/3.2 is also quite important, though new gaming consoles and computers are likely to upgrade to faster speeds over USB-C, so be prepared.

Gamers should look for auto-backup features and universal compatibility. Some models, like the Silicon Power Armor A60 drive, also have built-in storage for cables and military-grade protection, which may fit your requirements.

Finally, some drives, like the Seagate Game Drive family, are specifically designed to match PS4 colors while other models are optimized for Xbox.

Extra features

While all of the above features and specifications are worth considering before anything else, there are other aspects to look out for if you’re still unsure about which drive to choose.

Some offer better warranties than others, so if you are at all concerned about reliability, picking one with a long warranty is a good idea.

Also, consider the cable bundled with the drive. If your laptop or phone has USB-C or Thunderbolt 3 connections and your drive only comes with a USB-A cable, factor in buying another cable or an adapter.

Finally, some offer Wi-Fi connectivity for easy file access. These models typically include a rechargeable battery and a USB-based charger.

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