A factory reset wipes your personal files, accounts, and settings — but not the operating system itself

A factory reset removes the files, photos, documents, and accounts you added after you bought the device. It does not remove the operating system (Windows, macOS, Android, iOS) or the programs that came pre-installed from the manufacturer. When you reset, the device returns to the state it was in when it left the factory — which means your data is gone, but the core software that makes it run stays.

The confusion happens because "everything" feels like it should mean everything. It does not. A factory reset is a data wipe, not a software wipe. If you want to remove the operating system itself, you need a different process — usually called a clean install or a format, depending on the device type.

Key Takeaways

  • A factory reset deletes your personal files, photos, documents, passwords, and user accounts, but leaves the operating system and manufacturer software in place.
  • On Windows and Mac computers, a factory reset removes your user profile and files but keeps the OS; on phones and tablets, it removes everything you installed but keeps Android or iOS.
  • If you want to remove the operating system itself, you need a clean install (Windows/Mac) or a format (some Android devices), which is a separate process.
  • Before you reset, back up anything you want to keep — a factory reset is designed to be permanent and recovery is difficult or impossible.

What gets deleted during a factory reset

Your personal files disappear: documents, photos, videos, downloads, email messages, browser history, saved passwords, and any files you created or downloaded. Your user accounts and login information are removed. Any programs you installed are gone. Your wireless network passwords, paired Bluetooth devices, and custom settings all vanish.

On a Windows computer, this means your user profile is deleted, along with everything in your Documents, Pictures, and Downloads folders. On a Mac, your user account and its contents are removed. On an iPhone or Android phone, every app you downloaded, every photo you took, every text message, and every setting you changed disappears. The device returns to the state it was the day it arrived in the box.

What stays on your device after a factory reset

The operating system remains. Windows 10 or Windows 11 stays on your computer. macOS stays on your Mac. iOS stays on your iPhone. Android stays on your Android phone. These are the core software that run the device, and a factory reset does not touch them.

Pre-installed programs also stay. On Windows, built-in apps like Notepad, Calculator, and Settings remain. On a Mac, Safari, Mail, and other Apple apps stay. On an iPhone, Apple's default apps like Messages, Photos, and Settings are still there. On Android, Google apps and whatever programs came with your phone from the manufacturer are untouched. A factory reset only removes software you chose to install yourself.

The difference between a factory reset and a clean install

A factory reset removes your data and user accounts but leaves the operating system. A clean install removes the operating system itself and reinstalls it from scratch. On Windows or Mac, a clean install is what you do if you want a completely blank slate — the OS is gone and then reloaded.

Most people do not need a clean install. A factory reset solves the common problems: selling the device, giving it away, removing malware, or fixing performance issues caused by too many programs and files. A clean install is for people who want to completely replace the operating system, which is rare outside of IT professionals or people troubleshooting serious corruption.

How to back up before you reset

Before you factory reset, save anything you want to keep. On Windows, copy your Documents, Pictures, and Downloads folders to an external hard drive or cloud storage like OneDrive or Google Drive. On a Mac, use Time Machine to create a backup, or manually copy folders to an external drive. On an iPhone, use iCloud to back up your photos, contacts, and settings — go to Settings, tap your name, then iCloud, and turn on the items you want saved. On Android, go to Settings, find Accounts or Google, and make sure your photos and contacts are synced to your Google account.

Cloud storage is the safest option because you can access your files from any device later. External hard drives work too, but you need the drive with you to restore files. Do not rely on the device's built-in backup if you are about to reset it — those backups are usually stored on the device itself and will be deleted during the reset.

When a factory reset is the right choice

Reset your device if you are selling it or giving it away and want to remove your personal information. Reset if the device is running slowly and you suspect too many programs or files are the cause. Reset if you think the device has malware and you want a clean slate. Reset if you forgot a password and cannot recover it through normal means. Reset if you are handing the device to someone else and want them to start fresh.

Do not reset if you are trying to remove the operating system — use a clean install instead. Do not reset if you think the problem is with the operating system itself, like corrupted Windows files — a factory reset will not fix that. Do not reset if you are not sure what you are doing — ask someone who knows the device before you proceed, because the reset cannot be undone.

How to perform a factory reset on common devices

On Windows 10 or 11, go to Settings, select System, then Recovery. Click "Reset this PC" and choose whether to keep your files (it will not — this option is misleading) or remove everything. On a Mac, restart the computer, hold Command and R during startup to enter Recovery Mode, then select Reinstall macOS. On an iPhone, go to Settings, tap General, select Transfer or Reset, then choose Erase All Content and Settings. On Android, go to Settings, find System or About Phone, select Reset Options, and tap Erase All Data.

Each process takes 15 minutes to an hour depending on the device. The device will restart several times. Do not interrupt the reset or turn off the device while it is running — this can leave the device in an unusable state. After the reset completes, the device will ask you to set it up as if it were new, including creating a user account or signing into your Apple or Google account.

Frequently Asked Questions

Can I recover files after a factory reset?

Recovery is possible but difficult and not may provide. Deleted files sometimes remain on the storage drive until new data overwrites them. Specialized recovery software can sometimes retrieve them, but success depends on how much new data has been written since the reset. The longer you wait after resetting, the less likely recovery becomes. Do not count on recovery — back up before you reset.

Will a factory reset remove viruses or malware?

A factory reset removes most malware because it deletes all your installed programs and files. However, some sophisticated malware can hide in the operating system or firmware, which a factory reset does not touch. If you suspect serious malware, a factory reset is a good first step, but it is not a may provide. After resetting, reinstall only the programs you actually need and keep your antivirus software current.

Does a factory reset remove the operating system license?

No. On Windows, your license key remains tied to the device or your Microsoft account, so Windows will reactivate after the reset. On a Mac, your Apple ID is tied to the device. On an iPhone or Android phone, your Apple or Google account is what matters, not the device itself. After you reset and sign back into your account, your license and services reactivate automatically.

What if I reset the wrong device by accident?

Stop using the device when ready and do not add any new files or programs. The longer you wait, the more likely deleted data is overwritten and unrecoverable. Contact a data recovery service — they have specialized tools and may be able to retrieve your files if you act quickly. Recovery is expensive and not may provide, which is why backing up before you reset matters.

Can I undo a factory reset?

No. A factory reset is permanent. Once it completes, your personal files and accounts are gone. You cannot undo it through a straightforward menu option or keyboard shortcut. Your only option is data recovery software, which works only if you have not used the device since the reset. This is why backing up is critical before you reset.