Etoolio

Backup Audit (3-2-1 Rule)

Free backup checker. List your photos, documents and files, tick where each is stored, and see how they score against the 3-2-1 backup rule, including what exists in only one place and where sync is mistaken for a backup. Private.

List the data you would hate to lose, then tick everywhere each one is kept. This tool scores you against the 3-2-1 rule (3 copies, 2 kinds of media, 1 offsite) and flags the traps people miss: files that exist in only one place, and cloud sync being mistaken for a real backup. Nothing is uploaded; your list is saved only on this device.

Add data you care about

Start with your photos, or load the example list to see how the 3-2-1 rule scores a typical setup.

Are you actually backed up, or just hoping?

Most people believe their data is safe right up to the moment it is not. The photos are "in the cloud", the work files are "on the laptop", and it all feels fine, until a phone is lost, a drive dies, or a wrong tap deletes a folder that syncs the deletion everywhere. This free audit replaces that vague confidence with a clear answer. You list the data you would hate to lose, tick where each set is kept, and it scores you against the 3-2-1 rule, then flags exactly what to fix first. Nothing you enter leaves your device.

How it works

  • List what matters: photos, documents, work files, contacts, anything irreplaceable.
  • Tick where each copy lives: this device, another device, a drive, the cloud, offsite.
  • Get your backup health, with the single-copy files and sync-not-backup traps called out.

The 3-2-1 rule, in plain terms

The 3-2-1 rule is the backup standard that has protected data for decades: keep 3 copies of anything you care about, on 2 different kinds of media, with 1 of them offsite. Three copies, because any single one can fail. Two media types, because one kind of storage or one account can be wiped by a single fault. One offsite, because a fire, flood or theft is a single event that can take everything in one location at once. Meet all three and the everyday disasters simply cannot wipe you out.

Sync is not a backup

This is the trap that catches careful people. iCloud, Google Drive, Dropbox and OneDrive are sync services: they mirror your device so every copy matches. That is wonderful for convenience and useless as protection against your own mistakes, because a deletion or a ransomware attack is copied to every mirror within seconds. A real backup keeps separate, versioned copies you can roll back to. The audit flags any data whose only extra copy is a sync mirror, so you can add a proper versioned backup alongside it.

The copy that exists in only one place

The highest risk in most people's setup is data with a single copy, usually years of photos sitting only on a phone. One loss and it is gone with no way back. The audit surfaces every single-copy item as critical, because the fix is almost always quick and turns a potential permanent loss into a non-event. Start there, then work outward to two media types and an offsite copy.

Private by design, part of FailSafe

What you own and where you keep it is sensitive, so this tool is built so that it never leaves your device: everything runs in your browser and your list is saved only in your browser's local storage. This is part of FailSafe, tools that help you defend against your own digital fragility: what breaks if you lose a device, miss a deadline, or a single point of failure gives way. The last habit worth building is the simplest: test a restore, because an untested backup is only a hope.

Good to know

Backup Audit (3-2-1 Rule), frequently asked questions

What does the backup audit do?

It turns a vague worry, am I actually backed up, into a clear answer. You list the data you would hate to lose, tick everywhere each set is kept, and the tool scores you against the 3-2-1 rule, then flags the specific traps people fall into: files that exist in only one place, copies that are all in the same location, and cloud sync being mistaken for a real backup. You get a backup-health score and a prioritised list of what to fix first.

What is the 3-2-1 backup rule?

It is the long-standing standard for keeping data safe: keep at least 3 copies of anything you care about, on 2 different kinds of media (for example a drive and the cloud), with 1 of those copies stored offsite. The logic is simple: one copy can fail, so you keep three; one type of media or one location can be wiped by a single event, so you spread them out. Following it means the everyday disasters, a dead drive, a lost phone, a break-in, a bad tap, cannot take everything at once.

Why is cloud sync not the same as a backup?

Sync services like iCloud, Google Drive, Dropbox and OneDrive mirror your device: whatever you do on one copy happens to all of them, usually within seconds. That is great for convenience, but it means a mistake propagates too. If you delete a file by accident, or ransomware encrypts your folder, the deletion or encryption is copied everywhere almost instantly. A real backup keeps separate, versioned copies you can roll back to, so you can recover the file as it was yesterday. This tool flags data whose only extra copy is a sync mirror.

What does 'exists in only one place' mean, and why is it the biggest risk?

It means a set of data, often photos or work files, has just a single copy: on your phone, or on one laptop, and nowhere else. That is one failure away from being gone forever, and it is the single most common way people lose irreplaceable files. Devices are lost, stolen, dropped and simply die. The audit surfaces every single-copy item as critical, because making a second copy is usually quick and turns a permanent loss into a non-event.

How do I actually fix a weak backup?

Start with anything irreplaceable, like photos, and get it to three copies: the working copy, a second copy on a different kind of media (an external drive or a dedicated backup service), and a third copy offsite. Add a versioned backup alongside any sync so you can roll back mistakes, keep one copy in another physical location or a real cloud backup, and, just as important, test that you can actually restore a file before you ever need to. An untested backup is only a hope.

Is my list private?

Yes. Everything you enter is saved only on your device in your browser, and nothing is ever uploaded to a server. There is no account. The audit is designed so that the details of what you own and where you keep it never leave your device.

Is it free?

Yes, free with no signup, and it runs entirely in your browser.

Keep going

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