Ask where backups belong and you'll get three confident answers. Cloud people say the cloud, drive people say a drive on your desk, and someone will tell you to build a NAS. The cloud vs external drive argument is usually framed as a choice, and that framing is the problem: each option fails in a different way, and picking one means accepting that failure with nothing behind it.
The honest answer is that you want more than one. Here's how the three actually compare, and how to pick the combination that fits what you have.
They don't fail the same way
This is the part worth understanding, because it's what makes the comparison decidable. Cost and capacity are easy to look up. Failure modes are what actually decide where your files should live.
Cloud storage is offsite by default. That's its real feature, more than the convenience. If your home floods, your laptop is stolen, or a drive dies, the copy in Google Drive or Dropbox or Amazon S3 doesn't care. What it costs you is a monthly fee for as long as you want to keep the data, and a dependency on your connection and on the provider's account decisions. Cloud copies fail through billing and access: a lapsed card, a locked account, a service that changes its terms.
External drives are the cheapest way to hold a lot of data. One payment, no subscription, and copying a few hundred gigabytes takes minutes rather than a weekend of uploading. The catch is location. An external drive usually lives in the same room as the computer it's backing up, so anything that takes out one takes out both. Drives also fail silently: they sit in a drawer for two years, and the day you need them is the day you find out.
A NAS is a small always-on storage box on your home network. It's genuinely good at what it's for, which is several people or devices sharing a large library, always available, without paying per gigabyte forever. It's also the option that's equipment rather than a product. You maintain it, and it's still in your house, so it has the same location problem as an external drive with more moving parts.
Notice that two of the three fail for the same reason: they're in the building. That's the whole argument for the 3-2-1 approach, and if you want the reasoning in full, the 3-2-1 backup rule explained is the short version.
What each one is genuinely best at
- Cloud — the offsite copy. Non-negotiable if the files matter, because it's the only one of the three that survives something happening to where you live.
- External drive — bulk and speed. Large photo and video libraries where paying monthly for hundreds of gigabytes stops making sense.
- NAS — shared, always-on storage for a household or a large media collection. A convenience and capacity answer more than a backup answer, since it's still local.
So where should your backups live?
For most people, the practical answer is a cloud drive plus an external drive, and it isn't a compromise. It's two different failure modes covered by two cheap things. The cloud copy handles disasters that affect your home. The external drive handles the cost and speed problem that cloud storage has with large libraries.
Add a NAS if you have a reason beyond backup, like several people pulling from the same library. Adding one purely to have backups is buying equipment to solve a problem two simpler things already solved.
If you already have all three and you're unsure which direction files should move between them, backup vs sync is worth reading first, since choosing the wrong one is how people accidentally propagate a deletion everywhere instead of protecting against it.
Where Sync fits, and where it doesn't
Sync by Miciniti connects Google Drive, Dropbox, OneDrive, Box, Amazon S3, and USB and external drives in one app, so the cloud copy and the local copy are two tasks in the same place rather than two separate chores in two separate apps.
To be clear about the third option: Sync does not support NAS or network drives. If a NAS is part of your setup, it stays outside Sync. That isn't a workaround, it's a limitation worth knowing before you plan around it.
Setting up the two copies looks like this:
- Add your cloud service in Sync as a drive, and connect your external drive as another.
- Create a Backup task from the folder you care about to the cloud destination.
- Create a second Backup task from the same folder to the external drive.
- Run them. Each keeps the destination current without touching the originals.
Both tasks stay saved, so bringing either copy up to date later is one tap rather than a fresh setup. If you're not sure whether Backup or one of the mirroring operations is right for a particular job, the five sync modes explained covers when each one applies, including Full Sync, the only one that mirrors deletions.
Nothing runs on its own
Worth stating plainly, since it affects how you'd plan around this: Sync tasks run when you tap them. There's no background service watching your folders and copying as you work.
That's a real trade-off. You give up "set it and forget it," and in return nothing leaves your device without you, and nothing is quietly consuming your connection. In practice, running two saved tasks after a big import is the habit that matters, and it takes seconds.
What it costs
Connecting any one drive in Sync is free and ad-supported, which is enough for a single cloud backup. Connecting several drives at once, USB and external drive support, and an ad-free experience come with Sync's paid upgrade, available as a subscription or a one-time lifetime purchase. Since the recommendation here is a cloud copy and a local one, that's the tier the two-destination setup lands in.
Get Sync
Sync connects Google Drive, Dropbox, OneDrive, Box, Amazon S3, and USB and external drives from one app on iPhone and iPad, Android, Mac, and Windows. If you're setting this up from scratch, how to sync files to Google Drive, Dropbox and more walks through connecting your first destinations.
Frequently asked questions
Is cloud backup better than an external hard drive?
Neither is better in general, because they fail in different ways. Cloud storage is offsite by default, so it survives a fire, a flood, or a stolen laptop, but it costs money every month for as long as you keep it and it depends on your connection. An external drive is a one-time cost and much faster for large amounts of data, but it usually sits in the same room as the device it's protecting, so a single household disaster takes both. Most people are best served by one of each rather than a winner.
Do I need a NAS for home backups?
Most people don't. A NAS makes sense when you have a large media library, several people or devices sharing the same storage, or a genuine need for something always available on your home network. It's more expensive up front and it's equipment you maintain rather than a product you use. If your main concern is that your photos and documents exist in more than one place, a cloud drive plus an external drive gets you there for far less effort.
Does Sync work with a NAS or network drive?
No. Sync connects cloud services and local storage, including USB and external drives, but network drives and NAS devices are not supported. If a NAS is part of your setup, treat it as separate from Sync rather than something Sync manages, and use Sync for the cloud and external-drive side of your backups.
How many copies of my files do I actually need?
The usual guidance is three copies of anything you'd hate to lose, on two different kinds of storage, with one of them somewhere else. That sounds elaborate but in practice it's the original on your device, a copy on an external drive, and a copy in a cloud service. If that's too much to start with, two copies with one of them offsite already puts you ahead of nearly everyone.
Does Sync copy my files to these places automatically?
No. Sync tasks run when you run them. You set up a task once, choosing the source, the destination, and the operation, then tap it whenever you want to bring the destination up to date. There's no background process copying files as you create them, which means nothing moves without you.
What's the cheapest way to keep a second copy of everything?
For a one-time cost, an external drive is hard to beat, particularly for large photo and video libraries where cloud storage gets expensive as it grows. For an offsite copy, Amazon S3 is usually the cheapest per gigabyte if you don't mind a longer setup than a consumer cloud service. The trade-off is that the cheapest option is rarely the most convenient one, so weigh how often you'll actually use it.
