Most “I have backups” stories end the same way: someone has an external drive somewhere, or they think iCloud or OneDrive saves everything, and when their hard drive dies they discover the backup was either incomplete, outdated, or never actually ran.
Here’s how to actually back up your computer for free, plus the one step almost everyone skips.
The 3-2-1 rule for normal humans
The professional version is “three copies, on two different media, one off-site.” For home users, here’s what that looks like in practice:
- Your live data on your computer (copy 1)
- An automatic backup to either an external hard drive or cloud storage (copy 2)
- A second backup somewhere else — different cloud, different drive (copy 3 + off-site)
If a fire takes out your home, copy 1 and 2 are gone. Copy 3 saves you.
Free option 1: Use what’s built into your operating system
Windows: File History
- Plug in an external hard drive
- Settings → Update & Security → Backup → Add a drive
- Pick the drive, turn it on
- It runs automatically every hour and keeps versions of files
Mac: Time Machine
- Plug in an external hard drive
- System Settings → General → Time Machine → Add Backup Disk
- Pick the drive
- Runs every hour, keeps full system snapshots
Both are free, both work well, both run in the background. The external drive costs $40–$80 for 1–2 TB — plenty for most home users.
Free option 2: Cloud storage free tiers
For a second copy:
- Google Drive — 15 GB free, includes photo storage via Google Photos
- Microsoft OneDrive — 5 GB free, increases to 1 TB if you have Microsoft 365
- Dropbox — 2 GB free
- iCloud — 5 GB free, more if you have Apple devices
The free tiers are limited but enough for documents, scanned paperwork, and irreplaceable family photos. For full computer backups you need paid tiers ($2–$10/month).
The one step most people skip: TEST the backup
Setting up a backup is half the job. The other half: prove it actually works.
Once a year (or after any setup change), do this:
- Pick a file from your backup — any file
- Restore it to a different folder
- Open it. Make sure it actually works.
You’d be amazed how many people set up “backups” that never actually ran, or ran but didn’t include the files they thought.
A backup you’ve never restored is a hope, not a backup.
What to actually back up
Most people obsess about full system backups. For most home users, that’s overkill. Focus on what you can’t replace:
- Documents folder — work files, taxes, scanned paperwork
- Photos — the irreplaceable stuff
- Anything you can’t re-download — programs you can reinstall later, but personal files you can’t recreate
If your computer dies, you can buy a new one and reinstall the OS in an afternoon. You can’t replace your kids’ baby photos.
Beyond free: when a paid backup service is worth it
Free tiers are great for documents and irreplaceable photos. If you have more than ~15 GB to back up, or you want one service that handles everything (computer + phone + cloud accounts) without juggling, a paid backup service is usually a better fit than stitching free tiers together.
The one we use and recommend ourselves is iDrive — runs around $50–$80/year for several TB of storage, automatic continuous backup across multiple devices, encrypted, and you can restore from anywhere. (That’s an affiliate link — if you sign up through it, iDrive pays us a small commission. We linked it because we use it, not the other way around.)
Other reasonable paid options include Backblaze and Carbonite. They all do roughly the same thing — pick whichever pricing and interface you prefer.
When professional help makes sense
DIY backup works for most home users. Call us when:
- You have data on a failing drive that you need to recover (we have tools for this; pricing is case-by-case)
- You’re not sure your current backups actually work
- You want a more robust system — network-attached storage, automatic cloud backups, version history
Computer repair, including data recovery, is one of our most-requested home services. (732) 637-9640.