Reviews You Can Rely On

How We Tested External Hard Drives

Hard drives come in a variety of shapes, sizes, and materials. Even their interior electronic components can vary immensely. Before we got to transferring photos, music, and files, we meticulously scrutinized customer reviews and online forums for dozens of models. After evaluating and purchasing the best candidates for our review, we got down to business. We recorded hundreds of different data points and subjected every drive to durability tests to narrow our focus to three key metrics. Read below for a full rundown of our testing process.

external hard drive - our testing process always includes hundreds of hours of hands-on use.
Our testing process always includes hundreds of hours of hands-on use.
Credit: Aspen Rain Weaver

Read/Write Performance


A hard drive's primary purpose is to transfer data at the highest speeds possible between devices, so we decided that read and write performance should be the primary focus of our review. To begin testing each, we first devised a series of comprehensive tests to evaluate both Optimal and actual speeds. We determined Optimal speeds by using third-party software to test the highest speeds possible on a disk drive. For Windows, we used CrystalDiskMark, and for macOS, we used AmorphousDiskMark. We used the two software programs to gather data for two types of transfers: sequential and random. We also checked speed information on USB-C and USB-A ports. Sequential tests demonstrate the drive's ability to read an entire file from point A to point B. In contrast, random tests assess their capacity to access random data points throughout an extensive database.

external hard drive - using multiple different software and operating systems gives us...
Using multiple different software and operating systems gives us further insight into the range of functionality for each hard drive.
Credit: Aspen Rain Weaver

For each drive, we conducted three sequential speed read tests of 1GB, 4GB, and 8GB sizes, as well as three write tests of the same sizes, at a queue depth of 8 on both software platforms. With these 18 different readings, we then combined their respective results for the final average sequential read and write speeds. We then performed the same actions in a random read and write scenario at a queue depth of 64 to obtain average random read and write rates. For every hard drive, this yielded 12 final average rates in megabytes per second.

external hard drive - testing the sandisk extreme v2 using a windows computer and...
Testing the Sandisk Extreme V2 using a Windows computer and CrystaDiskMark software.
Credit: Aspen Rain Weaver

Our next portion of testing involved obtaining actual speed data. To accomplish this, we created a drag-and-drop test with three different file sizes: 1GB, 5GB, and 10 GB. We ensured that these compilations included a variety of file types to cover all bases, and then timed how long each one took to transfer from computer to hard drive. We again tested these file sizes three times and then calculated them into average speed rates. This actual speed testing provided us with a much deeper insight into how each drive performed under actual pressure and data transfer conditions.

external hard drive - while third-party software was helpful for an understanding of each...
While third-party software was helpful for an understanding of each drive's speed, our drag and drop test is what truly distinguished our winning products.
Credit: Aspen Rain Weaver

At this point, it is worthwhile to understand the differences between solid-state drives (SSDs) and hard disk drives (HDDs). SSDs utilize flash memory and have no moving parts, resulting in faster read/write speeds and increased ruggedness during impact. HDDs are a spinning disk and moving read/write heads, which ultimately makes them slower and more susceptible to damage; however, they come at a more reasonable price point for those on a budget. After days of reviewing numbers and documenting any mishaps or occurrences during transfer, it became clear which were leaders in logging large levels of data.

HDD vs SSD external hard drives.

Usability


In today's era of rapidly advancing technology, we strive to minimize the formatting, driver installation, and overall hassle associated with setting up a new device. That's why our team of tech testers decided our second most imperative portion of the score should come from Usability. For this section of our review, we looked at each drive directly out of the box.

external hard drive - some drives even come with their own carrying case and keypad...
Some drives even come with their own carrying case and keypad access, further adding a layer of protection to both your data and the physical drive itself.
Credit: Aspen Rain Weaver

We thoroughly checked and rechecked the compatibility capabilities of every hard drive across a wide range of systems, including macOS, Windows, Chrome, Android, and gaming consoles. Every drive comes with its own intended cable, so we used all the included connections, noting the type of cord and whether we needed an adapter. Our evaluation included researching the range of available storage options and poring over warranty information. We also took the time to note and utilize security features and recovery solutions to understand how well each product performs in securing sensitive information. After meticulously scrutinizing every detail that makes hard drives easier to use, we were finally able to tally final scores for each of our hand-selected portable storage devices.

external hard drive - the wd my passport portable is a simple, easy-to-use, and elegant...
The WD My Passport Portable is a simple, easy-to-use, and elegant piece of tech.
Credit: Aspen Rain Weaver

Portability


In today's era of remote work and home offices, transportability can be a significant factor when purchasing a new hard drive, which is why our final chunk of scores comes from our Portability metric. Whether you take your drive to and from work or are constantly traveling for your job, this metric might hold more or less weight when it comes to your next investment. That's why we spent countless hours diving into each unit's weight, size, and safety features.

external hard drive - weighing and measuring are two imperative data points for each hard...
Weighing and measuring are two imperative data points for each hard drive's portability score.
Credit: Aspen Rain Weaver

When evaluating a resilient hard drive, one of the first things we test is the manufacturer's claimed drop rating. We took every drive that can withstand impact and tested them to their stated limit, from several feet to several meters. Afterward, we plugged them in and noted whether they worked similarly to before. Next, we performed similar stress tests on all drives that claimed water resistance by flooding each unit in fresh water for 3 minutes, again testing afterward for consistent performance. We also noted what type of X-ray, dust, or magnetic resistance these products had, if any. Our following portability factors included the size, weight, and volume of each hard drive, so we weighed, measured, and calculated accordingly before awarding final scores.

external hard drive - one of the tester's favorite experiments is the water resistance test.
One of the tester's favorite experiments is the water resistance test.
Credit: Aspen Rain Weaver

Conclusion


We have enjoyed exploring the world of external hard drive technology over the past several years. We wholeheartedly stand by our testing process, scores, and award winners, and we hope you do too.

On the hunt for more great electronics reviews? Check out our side-by-side analysis of home electronics. For more storage solutions, consider microSD cards or USB flash drives.