A factory reset erases your personal files, accounts, and settings, but leaves the operating system and pre-installed apps intact

A factory reset wipes your device back to the state it left the manufacturer. This means your photos, documents, messages, browsing history, saved passwords, and any apps you installed will be gone. Your email accounts, social media logins, and custom settings disappear too. What remains is the operating system itself (Windows, macOS, iOS, or Android) and whatever apps came with the device originally.

The key distinction: a factory reset is not the same as physically destroying the device's storage. The data is marked as deleted and the space is freed up for new files, but recovery software can sometimes retrieve it afterward — especially if you do not overwrite that space first. If you are selling or giving away the device, this matters.

Key Takeaways

  • A factory reset removes all your personal files, photos, messages, and installed apps, but keeps the operating system and manufacturer apps.
  • Your saved passwords, browser history, email accounts, and login credentials are erased during a factory reset.
  • Deleted files can sometimes be recovered with specialized software unless you overwrite the storage space afterward.
  • Before resetting, back up anything you want to keep — photos, documents, or settings — because the process cannot be undone.

What gets deleted during a factory reset

Your personal data vanishes completely: photos, videos, documents, spreadsheets, PDFs, and any other files you created or downloaded. Text messages, email messages stored locally on the device, and call logs are removed. Browser bookmarks, saved passwords, and browsing history disappear. Any apps you installed from the app store or sideloaded are gone.

Your accounts and logins are also erased. If you signed into Gmail, Outlook, Facebook, or any other service, those login sessions end and the cached data is removed. Custom settings you changed — display brightness, notification preferences, keyboard layout, accessibility options — revert to factory defaults. Wallpapers, ringtones, and themes you added are deleted.

On a Windows PC, this includes files in your Documents, Downloads, Desktop, and Pictures folders, plus anything in your user profile. On a Mac, files in your home directory are removed. On an iPhone or Android phone, your photos, contacts, and app data all go. External storage like an SD card may or may not be wiped depending on the device and reset method — this varies by manufacturer.

What stays on your device after a factory reset

The operating system itself remains. Windows, macOS, iOS, or Android is reinstalled fresh, as if the device just came from the factory. Pre-installed apps that came with the device stay in place — on an iPhone, this means Apple's built-in apps like Mail, Calendar, and Maps. On an Android phone, Google's apps and any apps your phone manufacturer pre-loaded remain. On Windows, built-in apps like Notepad and Settings stay.

The firmware — the low-level software that controls the device's hardware — is not affected. Your device's serial number, IMEI (on phones), and hardware identifiers remain the same. The device will function exactly as it did when new, except without your personal data and customizations.

How to back up before resetting

On an iPhone, open Settings, tap your name at the top, then tap iCloud. Turn on iCloud Backup and tap Back Up Now. This saves your photos, messages, settings, and app data to Apple's servers. You can also plug into a computer and use Finder (Mac) or iTunes (Windows) to create a local backup file.

On Android, open Settings, tap Accounts, select your Google account, and tap Account services. Choose Manage your Google Account, then tap the Backup tab. Turn on backup for your photos, messages, and app data. Some Android phones also offer a local backup option through Settings > System > Backup.

On Windows, use File History or System Image Backup. Open Settings, go to System > Storage > Advanced storage options > Backups, and turn on Backup now. This backs up your files to an external drive or cloud storage. On Mac, use Time Machine: plug in an external drive, open System Settings > General > Time Machine, and click Set Up.

For files you want to keep, copy them to cloud storage like Google Drive, OneDrive, Dropbox, or iCloud Drive before resetting. This ensures you can access them from any device afterward.

Deleted files can sometimes be recovered

When you factory reset a device, the files are not physically destroyed — they are marked as deleted and the storage space is marked as available for new data. Until that space is overwritten with new files, recovery software can sometimes retrieve the deleted data. This is true for phones, tablets, and computers.

If you are selling or donating the device, this is a security concern. Someone with the right tools could potentially recover your photos, documents, or login information. To prevent this, you can overwrite the storage space after resetting. On Windows, use the Cipher command in Command Prompt to securely erase free space. On Mac, use Secure Empty Trash or erase the drive using Disk Utility before selling. On iPhones and most modern Android phones, a factory reset followed by filling the storage with large files (then deleting them) makes recovery much harder.

Why you might factory reset your device

A factory reset solves persistent software problems: if your device is freezing, crashing, running slowly, or behaving erratically, a reset often fixes it by removing corrupted files or conflicting apps. It is also the standard step before selling, trading in, or giving away a device, because it removes all your personal information.

Some people reset to start fresh after years of accumulated apps, files, and settings that have slowed the device down. Others reset after a malware infection to ensure the malicious software is completely removed. If you forgot your password and cannot recover it through normal means, a factory reset can let you set a new one — though you will lose access to encrypted data.

The factory reset process varies by device

On an iPhone, go to Settings > General > Transfer or Reset > Erase All Content and Settings. You will be asked to enter your Apple ID password and confirm. The process takes 5 to 15 minutes.

On Android, the path depends on your manufacturer, but usually it is Settings > System > Reset options > Erase all data (factory reset). Some phones call it Settings > About phone > Reset > Factory reset. You may need to enter your PIN or password to confirm.

On Windows, go to Settings > System > Recovery > Reset this PC. Choose whether to keep or remove your files (if you choose remove, everything goes). Windows will ask whether to download a fresh copy of Windows or use the version already on your device. The reset takes 20 to 60 minutes depending on your device.

On Mac, restart the computer and hold Command + R to enter Recovery Mode. Open Disk Utility, select your drive, and click Erase. Then reinstall macOS from the recovery menu. This process takes 30 to 90 minutes.

Frequently Asked Questions

Can I undo a factory reset?

No, a factory reset cannot be undone. Once you confirm the reset, the process begins and your data is marked for deletion. This is why backing up beforehand is essential. If you have a backup from before the reset, you can restore from it after the reset completes, but the reset itself is permanent.

Will a factory reset remove viruses or malware?

A factory reset removes most malware because it deletes all installed apps and personal files where malware typically hides. However, some sophisticated malware can hide in the firmware or boot sector, which a standard factory reset does not touch. For maximum security when dealing with suspected malware, research whether your specific device offers a secure or deep reset option.

Does a factory reset delete files on an external hard drive or SD card?

Usually not. A factory reset typically only wipes the device's internal storage. Files on an external USB drive, SD card, or cloud storage remain untouched. However, some devices offer the option to wipe external storage during the reset process, so check the confirmation screen carefully before proceeding.

What happens to my apps after a factory reset?

Apps you installed from the app store are deleted, but you can reinstall them afterward using your existing account. If you signed into the app store with your Apple ID or Google account before resetting, you can download your previously purchased apps again at no cost. App data and settings within those apps are lost unless you backed them up beforehand.

How long does a factory reset take?

On a phone, expect 5 to 20 minutes. On a computer, expect 20 to 90 minutes depending on storage size and device speed. The device will restart multiple times during the process. Do not interrupt it or turn off the device while the reset is running, as this can leave the device in an unusable state.