How to restore an iphone to factory?

To restore an iPhone to factory settings, open Settings, tap General > Transfer or Reset iPhone, select Erase All Content and Settings, and follow the on-screen prompts to confirm.3 Ways to Restore an iPhone to Factory Settings1.Restore via iPhone Settings:Method 1 (On-Device).Open Settings, tap General, scroll down to Transfer or Reset iPhone, select Erase All Content and Settings, tap Continue, enter your device passcode or Apple ID password, and tap Erase iPhone.2.Restore via Mac (Finder) or Windows (iTunes / Apple Devices):Method 2 (Computer).Connect your iPhone to a computer via USB cable. Open Finder on Mac or iTunes / Apple Devices app on PC, select your iPhone from the sidebar, click Restore iPhone, and confirm to download fresh iOS firmware and wipe the device.3.Restore Frozen or Disabled Device:Method 3 (Recovery Mode).Connect your iPhone to a computer. Put it in Recovery Mode (press Vol Up, Vol Down, then press and hold Side button until the computer screen icon appears). On your computer screen, select Restore when prompted.Restoring via Settings vs. Restoring via ComputerRestore MethodRequires Internet Connection?Installs Fresh iOS System Firmware?Best Used ForSettings (Erase All Content)Yes (To disable Activation Lock)No (Wipes user data, keeps current iOS version)Selling, trading in, or gifting your iPhoneMac / PC (Finder / iTunes)Yes (Downloads full iOS software package)Yes (Overwrites corrupt system files completely)Fixing severe software bugs, boot loops, or system crashesRecovery Mode RestoreYesYesResetting forgotten passcodes or disabled screensPre-Restore Checklist: What to Do FirstBack Up Your Data: Go to Settings > [Your Name] > iCloud > iCloud Backup and tap Back Up Now to save photos, contacts, and app data.Turn Off Find My: Go to Settings > [Your Name] > Find My > Find My iPhone and toggle it Off to remove Activation Lock.Unpair Accessories: Unpair your Apple Watch in the Watch app to save a fresh backup of your watch data before wiping.