Sooner or later everyone wonders whether to buy an external hard drive once or pay for cloud storage every month. The honest answer is that they fail in different ways and are good at different things, so the decision is really about which risks you're more worried about.
The comparison at a glance
| External hard drive | Cloud storage | |
|---|---|---|
| Cost model | One-time purchase; replaced every few years | Ongoing monthly or yearly fee; free tiers exist |
| Speed for large transfers | Fast: USB 3 drives commonly move 100 MB/s or more | Limited by your internet connection, especially upload speed |
| Protects against laptop failure | Yes | Yes |
| Protects against fire, flood or theft at home | No, if kept next to the computer | Yes, the data is stored elsewhere |
| Protects against accidental deletion | Only if the backup software keeps history | Yes, if the service keeps versions or a recycle bin |
| Access from anywhere | No | Yes, from any device with a browser or app |
| Main weaknesses | Mechanical failure, loss, theft, forgetting to plug it in | Internet dependence, account problems, ongoing cost |
The speed gap is bigger than people expect
A first backup is where the difference is starkest. Copying 500GB to a USB 3 hard drive at around 100 MB/s takes roughly an hour and a half. Uploading the same 500GB over a 20 Mbps upload connection takes about two and a half days of continuous transferring. Many home connections have far slower uploads than downloads, so a large first upload can stretch over days or weeks.
Restores work the other way around. If your laptop dies, copying everything back from a local drive is fast, while downloading hundreds of gigabytes from the cloud depends on your connection. That's a good reason to keep a local backup for bulk restores even when cloud storage is your offsite copy.
How each option fails
External drives
Hard drives are mechanical devices. Large-scale studies from data-center operators have reported annual failure rates in the low single-digit percentages for drives in service, rising as they age, and a drive that travels in a bag or gets knocked off a desk is at greater risk. Solid-state drives have no moving parts, but one left unpowered for long periods can gradually lose data, so neither type is a good place to leave your only copy in a drawer for years. Drives can also be stolen, lost, or simply forgotten.
Cloud storage
Cloud services run on professionally managed, redundant hardware, but they carry their own risks: an account that's locked or suspended, a forgotten password without recovery options, an outage, a pricing change, or a lapsed subscription that leaves your data at risk of deletion after a grace period. You also depend on a working internet connection to get at your files.
Which one should you choose?
For anything important, don't choose. Use both, which is exactly what the 3-2-1 backup rule recommends: your working copy on the computer, a second copy on an external drive, and a third copy offsite in the cloud. If you can only pick one, these guidelines help:
- Choose a drive first if you have a large archive (several terabytes of video, say), a slow upload connection, and mainly need protection from hardware failure.
- Choose cloud first if you travel, work across several devices, share files with other people, or your main worry is theft, fire or flood.
- Choose both if losing the files would cost you money, clients or irreplaceable memories.
Getting the most from an external drive
- Buy two rather than one, and keep one at a different location such as a relative's house or your office, swapping them every month or so.
- Don't leave the drive permanently connected. Connect it, run the backup, then disconnect it, which also limits ransomware exposure.
- Write the purchase date on the drive and plan to replace it after three to five years rather than waiting for it to fail.
- Check the drive's health status now and then using the tools your operating system provides.
- Use backup software that keeps several versions of files, not just a copy of the latest state.
Getting the most from cloud storage
- Upload the irreplaceable things first: documents, photos and finished work. Bulk archives can follow.
- Start the first upload on a wired connection and let it run overnight; resumable uploads let it continue after interruptions.
- Enable multi-factor authentication and set up account recovery so you can't get locked out.
- Check how long deleted files and old versions are kept.
- Keep a periodic local copy of your most critical folders so you're never fully dependent on one provider.
The cheapest sensible setup for most households is a single external drive plus a free or low-cost cloud tier for the files that can't be replaced. You can always add capacity later, but you can't add a backup after the disk has already failed.