Buying the best-value external hard drive or SSD is, strictly speaking, a numbers game. The biggest numbers in play? The first is the price you pay on any given day for the drive you’re considering. Since Amazon Prime Day 2024 is nearly upon us, it's one of the best times of the summer, let alone the year, to make your purchase.
The second number to look out for is the capacity of the drive, in gigabytes. Simple math will tell you how much you're paying per gigabyte, which is an excellent yardstick for measuring whether a drive is a scorcher of a deal or a just “meh” one.
Those are not the only numbers to know, though. Also look at the length of the warranty for any drive you’re eyeing. Plus—and here’s where yours truly, the PCMag experts, come in—check out formal speed-test numbers from reputable third-party review sites. We’ll toot our horn: We test dozens of external drives every year, both classic platter-based hard drives and speedy, compact solid-state models. A low cost per gigabyte, plus a warranty plan you can live with and a speed rating high enough for the kinds of stuff you store, together add up to the right external drive for your laptop or desktop.
Deals on external storage move whip-fast in and out of “good deal” and “great deal” territory—the very best ones don't stick around for long. That’s because everybody loves more gigabytes. Here are some of the best deals we've seen pre-Prime Day on the top drives we’ve tested. (See also plenty of other deals you can land before the main event.)
Superbly suited for pro content creators and mainstream users alike, the Samsung SSD Portable T9 is not only a Prime Day deal, but it’s a great external SSD at any price. With the T9, you can expect 10Gbps speeds with the USB-C ports on most laptops and desktops. And if you’re fortunate enough to have a USB-C port that supports USB 3.2 Gen 2x2, you could see up to double that. The drive comes in capacities up to 4TB, and it supports 256-bit AES hardware-based encryption in the event it falls into the wrong hands. It’s also drop-proof and equipped with Samsung’s polished, handy Magician software utility. (See our review of the Samsung Portable SSD T9.)
Portable hard drives based on 2.5-inch internal platter mechanisms just recently hit a peak capacity of 6TB, so this deal on a 5TB model is for the kind of drive that, until not that long ago, was the roomiest around. We gave the My Passport 5TB an Editors’ Choice award, in its time, for its then-top capacity and lightweight design. WD’s supporting software is also a plus, and SSDs just can’t touch this drive’s cost per gigabyte of less than 3 cents. (See our review of the WD My Passport 5TB.)
You need to go all in on the T7 Shield only if you'll be taking your SSD places where most tech fears to tread. This drive has a rubbery wrapper that keeps it safe in the event of tumbles, rain, and other environmental invaders. Indeed, the T7 Shield is rated for dust- and water-resistance that should suffice for most casual (or should we say careless?) use. On-the-go photographers, field workers, and hopeless klutzes will want to give this tough drive a strong second look. It's a little costlier per gig than your typical external SSD, but if you can't put a value on your data, it's a bargain at any price—and especially at this one. (See our review of the Samsung Portable SSD T7 Shield.)
The Two Main Kinds of Drive: Paging HDDs and SSDs
External drives for consumers that you'll see on Prime Day are split into two broad categories: external SSDs (which have no moving parts), and external platter hard drives (based on spinning mechanical disks). Within the hard drive class are portable USB-powered drives, as well as larger, AC-powered (but still USB-connected) desktop models. Portable hard drives are built around the 2.5-inch drive mechanisms that once were common in laptops, and these top out at 5TB or 6TB. Desktop drives employ meatier, but roomier, 3.5-inch mechanisms; most of these nowadays start at 8TB. When choosing between desktop and portable drives, consider whether you'll have your drive sit in one place all the time, or if it needs to come with you on the road (or even just around the house).
Most mainstream external drives rely on the USB interface, in one of its myriad flavors. The drive may have a USB-A or USB-C connector at the computer end; many now come with both types of cables, or with an adapter. The nomenclature and nuances around USB speed specs are fussy stuff, so the best advice: Match the specific USB spec that the drive supports (say, "USB 3.2 Gen 2") with that of the fastest USB port on your PC or Mac. A few, usually pricey-per-gig, models employ the Thunderbolt 3 or 4 interface. These mostly target Mac users.
Looking for more deals? Then keep an eye on our up-to-the-minute Amazon Prime Day 2024 Deals coverage.