Our editors pick the products and services we write about. When you buy through our links, ZDNet may earn a commission.

Best external hard drive 2021: Top SSDs and storage

Back in 1981, storage prices ranged up to $50/MB. Today you can get deals at $15/TB, more than a three million times improvement. Here are the best options, sorted by price from low to high.

Storage is what makes your system your system. Almost as important, it can also dramatically expand the quantity and velocity of work you can do. Likewise, poor storage choices can cripple a system. 

The storage landscape today is more varied than ever before. Screaming performance? Dirt-cheap bit bucket? Fingernail form factor? Ginormous capacity? The choices can be daunting to sort out.

Most notebooks today come with solid-state drives (SSDs) that, because of cost, may only have 256GB or 512GB of storage space. Fortunately, with USB 3.1 and Thunderbolt interfaces, it's easy to add storage that is as performant as internal drives were just five years ago. 

There are great storage options for every workload. Here are, in my experience, the best.

SanDisk 512GB Ultra Fit USB 3.1

Almost invisible


A fingernail-sized USB-A drive for easy capacity expansion. Plug it into your Windows or Mac system, and the new capacity is instantly available. 

Best for supplementary storage of files under 100MB -- which most are -- since the transfer rates are lower than larger drives.

WD 5TB Elements Portable External Hard Drive HDD USB 3.0

A very good deal

Western Digital

Today, the low-cost hard drive sweet spot is in the 4-5TB range. This Western Digital drive is a good deal at $20 a terabyte. 

Powered by the USB port, no external power. Compatible with PC, Mac, PS4 & Xbox.

LaCie Rugged Mini 5TB External Hard Drive Portable HDD USB 3.0

Tougher than the rest


2.5" hard drives are remarkably tough, and this LaCie model builds in even more shock, crush, and rain resistance. I carried one for years with no problems. 

If you are hard on your equipment -- is your phone screen cracked? -- this is well worth the added cost of the rubber bumper and shock mounting this drive offers. 

CalDigit Tuff Nano 1TB SSD

Tough and tiny


If you are really hard on your gear, this is the external SSD for you. The Tuff Nano is IP67 certified to be waterproof, shockproof, and dust resistant. With real-world performance up to 900 MB/sec, this tiny drive - 3" x 2.2" x 0.6" -- is a dream for on-the-go professionals.

I've used other CalDigit products for years and have been pleased with their quality and performance. The ratings for this product bears this out.

Seagate Expansion 16TB External Hard Drive

Big and fast


Sometimes you need a lot of capacity. This drive has you covered. I've had the 8TB version on my desk for the last 3 years, and it's been solid.

You'll be pleasantly surprised to see how much faster it is than 2.5" drives, thanks to higher RPM and more read/write heads moving data in parallel, even with the same USB 3.0 interface.

It requires wall power and is not a drive to throw in a backpack. But in an office environment, drives of this class have shown an annual failure rate of about 1%. Still, make sure to have a local and/or cloud backup. 

It comes with one year of Seagate's Rescue Data Recovery Services, but that could take a few weeks.  

Is external storage good for backup?

Storage expansion has another plus: backup. I've been in the storage business for over 30 years, and I've heard a lot of horror stories. I maintain a daily local backup and a daily cloud backup and recommend that all professionals do the same. An external drive is a great place for a local backup.

Whatever you choose, remember that all storage fails. There is no substitute for regular backups, both local and to a cloud. Local gets you back up quickly. Cloud will enable you to recover from a serious local disaster.   

What specs are most important when shopping for external storage?

When looking at the options, don't worry too much about the spec numbers for transfer rates. Vendors frequently use the interface bandwidth for their "up to" hero number, a number you aren't likely to see in real life, especially if you aren't working with multi-gigabyte files. 

The key spec to look at is the device interface, generally SATA or PCIe and/or NVMe. SATA throttles a drive to no more than 500MB/sec -- which is more than most hard disk drives (HDDs) are capable of -- while PCIe and NVMe get into the 1-5GB/sec range, which is where higher-end SSDs shine.  

Which external storage is best for your needs?

We are living in the golden age of external storage. The range of options is the greatest it's ever been. Reliability has never been better, and I expect to see more Thunderbolt -- a higher performance interface -- drives arrive in the next year. 

I've stuck to recommending products of vendors I've tried. With over 25TB of external storage on my desk, that's probably more experience than most. 

The decision points will include mobile vs desktop, bus power or wall power, and SSD vs HDD for most folks. HDDs offer much lower cost capacity, slower access times, and use more power, while SSDs are much more costly, smaller, faster, and sip power. 

If you are a pro user, don't stint on your mobile storage and backup. Your work is way more valuable than the media you keep it on.

Comments welcome. What has worked well for you?