The simplest backup is an external hard drive and Windows Backup

The fastest way to protect your files is to plug in an external hard drive and let Windows do the work for you. Windows 10 and Windows 11 both have a built-in backup tool called File History that copies your documents, photos, videos, and desktop to an external drive automatically — you set it once and it runs in the background.

Buy an external hard drive (1 or 2 terabytes is enough for most people) from any electronics store, plug it in, and Windows will usually offer to set up File History right away. If it doesn't, go to Settings > System > Storage > Advanced Storage Options > Backup Options and turn on File History. Point it at your external drive and choose how often you want it to back up — daily is the default and works well.

This protects you against hard drive failure, accidental deletion, and ransomware that locks your files. It does not protect you if your house floods or burns down, and it does not back up your operating system — if Windows itself breaks, you'll need to reinstall it separately.

Key Takeaways

  • An external hard drive with Windows File History is the cheapest and easiest backup for most people, costing $50 to $100 and requiring almost no maintenance.
  • File History backs up your personal files but not Windows itself, so you'll need a separate system image if you want to restore your entire computer.
  • A system image (created with Windows Backup or a third-party tool) lets you restore your whole computer including Windows, programs, and settings, but takes much longer to create and restore.
  • Cloud backup through OneDrive, Google Drive, or Backblaze protects against physical disasters like fire or theft, but costs money monthly and is slower than a local drive.
  • The safest approach uses two backups: an external drive for speed and a cloud service for protection against loss of the physical drive.

Creating a full system image if you need to restore everything

If your hard drive fails completely, File History alone won't help you — you'll have to reinstall Windows and all your programs from scratch. A system image is a complete copy of your entire hard drive, including Windows, your programs, and all your settings. Restoring from a system image puts your computer back exactly as it was.

Windows 11 includes a tool called Backup (Settings > System > Backup) that can create a system image to an external drive. Windows 10 uses a tool called File History plus a separate System Image backup (search "Create a system image" in the Start menu). Both take an hour or more the first time, depending on how much data you have, but they only need to run once — you only restore from them if something goes seriously wrong.

Third-party tools like Macrium Reflect (free version available) and Acronis True Image do the same thing and often run faster. They cost money, but some people prefer them because they're easier to schedule and they work on both Windows and Mac.

Using cloud backup for protection against theft or disaster

An external hard drive sitting next to your computer won't help if your house burns down or your laptop is stolen. Cloud backup — storing copies of your files on a company's servers over the internet — protects against that. The trade-off is that it's slower, it costs money every month, and you're trusting a company with your data.

OneDrive (Microsoft's service, included free with Windows) backs up your Documents, Desktop, and Pictures folders automatically if you turn it on. Google Drive does the same if you use a Google account. Both give you 5 to 15 gigabytes free, which is enough for documents and photos but not for video or large media libraries. If you need more space, you pay roughly $2 to $10 per month depending on how much you store.

Backblaze is a dedicated backup service that costs about $7 per month and backs up your entire computer automatically — every file, every folder, everything. It runs in the background and uploads only the changes, so after the first backup it's fast. Carbonite and IDrive are similar services with slightly different pricing and features.

Cloud backup is slow on the first run (it can take days or weeks to upload everything), but after that it only uploads changes. If you need to restore, you read files one at a time or request a hard drive shipped to you, which takes longer than restoring from a local external drive.

Deciding between local and cloud backup

A local external drive is fast and cheap but vulnerable to fire, flood, or theft. Cloud backup is slow and costs money but survives physical disasters. The best protection uses both: an external drive for daily backups you can restore in minutes, and a cloud service for protection against losing the physical drive.

If you have a small amount of data (under 100 gigabytes of documents and photos), cloud backup alone through OneDrive or Google Drive is probably enough — it's free or very cheap and you don't have to buy hardware. If you have a lot of data or you need to restore quickly, start with an external drive and add cloud backup later. If you have irreplaceable files (family photos, business records, creative work), use both from the start.

Setting up automatic backups so you actually use them

The biggest reason backups fail is that people set them up once and then forget about them. File History and cloud services run automatically, so they work without you thinking about them. System images don't — you have to remember to create a new one every few months.

If you use Windows Backup or a third-party tool for system images, set a calendar reminder to run it quarterly or after major changes (installing new software, updating Windows). Write down where your backups are stored — the external drive name, the cloud service name, the login information — and keep that list somewhere you can find it if your computer breaks. If you ever need to restore and you can't remember where your backups are, they won't help you.

Test your backup once by restoring a single file from it. This takes 10 minutes and tells you whether your backup actually works before you need it in an emergency.

What not to back up and why

Some files don't need to be backed up because they're already stored somewhere else or they'll slow down your backup. Don't back up your web browser cache, temporary files, or the Windows folder itself — Windows Backup and most cloud services skip these automatically. Don't back up files that are already in cloud storage like Dropbox or OneDrive unless you want two copies.

If you use a cloud service like OneDrive, Google Drive, or Dropbox for your working files, those are already backed up by the company — you don't need a separate backup for them. But you should still back up files that live only on your computer: your Documents folder if it's not synced to the cloud, your email if you read it locally, your photos if they're not in Google Photos or OneDrive.

Backup for Mac and Linux computers

Mac computers have Time Machine, which works exactly like Windows File History — plug in an external drive and it backs up automatically. You can also use iCloud+ (Apple's cloud service) to back up Documents and Desktop. Third-party tools like Backblaze and Carbonite work on Mac too.

Linux has many backup options depending on which version you use. The simplest is to use a cloud service like Backblaze or to copy your home folder to an external drive using a tool like Timeshift. Linux users often have more technical options available but fewer automatic tools, so you may need to set up backups manually or write a script.

Frequently Asked Questions

How often should I back up my computer?

File History and cloud backup run automatically, usually daily or weekly — you don't have to think about it. System images should be created every few months or after major changes like installing new software or updating Windows. The more often you back up, the less data you lose if something goes wrong, but automatic backups handle this for you.

Can I back up to the same hard drive my computer uses?

No. If your hard drive fails, a backup on the same drive fails with it. You need an external drive, a cloud service, or both. Backing up to a different folder on the same hard drive protects you against accidental deletion but not against hardware failure.

What size external hard drive do I need?

For most people, 1 or 2 terabytes is enough. If your computer's hard drive is 500 gigabytes, a 1-terabyte external drive gives you room for multiple backups over time. If you have lots of video or photos, 2 terabytes is safer. Larger drives cost more but last longer before you run out of space.

If I back up to the cloud, do I still need an external drive?

Cloud backup alone works if you only care about protecting against loss of your physical computer. An external drive is faster to restore from and doesn't depend on your internet connection. Using both gives you the fastest restore (the external drive) and the best protection against disaster (the cloud).

What happens if I lose my password to my cloud backup?

You won't be able to access your files. Write down your cloud backup login information and store it somewhere safe — a password manager, a locked drawer, or a trusted person. If you lose it, the cloud service can help you reset it, but the process takes time and may require proof of identity.