The best external desktop hard drive

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After 20 hours of new research and testing, we found the best external desktop hard drive for most people is Seagate's 4 TB Backup Plus Desktop Drive. The Backup Plus has a great balance of speed and price and enough space for your future storage needs.

Who this is for

If you're not backing up the important documents and photos on your computer, you should start. Take a few minutes to set up a system that will back up your files automatically to an external hard drive and the cloud. Your computer's internal drive will stop working someday, and backing up solely to an external drive isn't a bulletproof strategy to protect yourself from data loss.

You should consider replacing your backup drives between the third and sixth year of use. If your drive dies and you have a cloud backup, you won't lose data, but restoring from the cloud will take a very long time (and probably blow through your monthly data cap). If you don't, well, say bye to your stuff. According to statistics from cloud backup service Backblaze, hard drives are most likely to fail either within the first 18 months of use or after three years.

How we picked and tested

We started with a list of 14 current desktop hard drives, and we used data from an early 2016 survey of Wirecutter readers to guide our research. Of 183 respondents, 55 percent said they'd like to spend less than $200 on a hard drive, and a third favored drives under $150. About a third of respondents said they needed 2 TB or 3 TB drives, and another third wanted 4 TB or 5 TB models. So we tested mostly 4 TB and 5 TB models, which met most respondents' price requirements, and still left plenty of additional capacity for future storage needs. The 8 TB models usually have better prices per terabyte, but they're costly and have more storage than most people need.

After narrowing our list of finalists by price and capacity, we tested seven desktop hard drives. For each one, we ran HD Tune Pro, a benchmarking program that tests transfer speeds, access time, burst rate, and CPU usage across the entire disk. You can read a more in-depth explanation of the program on the HD Tune website. We also timed a series of file transfers—a 7.07 GB folder of photos, a 19.7 GB music collection, and a 45.5 GB rip of a Blu-ray movie—from start to finish, running each transfer three times and determining the average to rule out performance hiccups.

To spot any widespread reliability issues, we read through Amazon reviews for each of the drives we tested, and counted the number of drive failures reported by users. This method has shortcomings—see our full guide for more on how we picked.

We also looked at Backblaze's hard drive reliability ratings from the first half of 2016, which are based on over 68,000 drives used in its cloud backup servers. Backup servers are a very different environment than a box on your desk—bare drives in servers are accessed more often and are subject to more vibrations and more heat; drives in desktop enclosures have more potential points of failure between the power connector, the USB connector, and the USB-to-SATA logic board. Even so, the Backblaze study is the largest, most recent sample of hard drive failures we have access to.

Our pick: 4 TB Seagate Backup Plus Desktop

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