TL;DR:
Want to know how to unlock a stolen iPhone when you don't know the passcode? The following three methods may help:
Just bought a second-hand iPhone online, only to find that it arrived with a passcode lock? In this case, you may suspect that the device is lost or stolen. If you want to use the iPhone instead of spending more time and money returning it and buying another one, you may wonder: Can a stolen iPhone be unlocked? And if so, how do you unlock a stolen iPhone?
This guide will explain three ways to unlock an iPhone when you don't know its passcode. If the iPhone is yours and you simply forgot the passcode or got locked out for another reason, you can also use the methods below to regain access to the device.

Yes, a locked iPhone can generally be erased to remove its screen passcode, but this does not necessarily make a stolen or lost iPhone usable. If the device is still linked to the previous owner's Apple account and protected by Activation Lock, you will need the original owner's credentials or their help to remove the lock before the iPhone can be activated normally. (How to remove Activation Lock without previous owner?)
If you legitimately own the iPhone or have recovered it with permission to use it, forgetting the screen passcode does not mean the device is permanently inaccessible. You can erase and restore it using the methods below. Keep in mind that these methods may delete all existing data on the iPhone.
The most effective way to unlock an iPhone would be using a third-party software called iOS Unlock. It is a professional and secure unlocking tool that helps you unlock iPhone without knowing the passcode. The whole unlocking process is smooth and easy. With this tool, you can bypass the lock screen on iPhone with a few clicks.
Key features of iOS Unlock:
Guide on how to unlock a stolen iPhone using iOS Unlock:
01Launch iOS Unlock on your computer. From the main interface, choose "Unlock Screen Passcode" and click "Start to Unlock". Connect your locked iPhone to the computer with a USB cable and continue as instructed by the program.

02Follow the on-screen instructions to put the iPhone into Recovery Mode or DFU Mode. After the program recognizes the device, select a location for the firmware package and click "Download" to download the required firmware.

03Once the firmware has been downloaded, click "Unlock". Carefully read the warning displayed on the screen, enter "000000" to confirm the operation, and click "Unlock" again.

04Wait until the process is completed. Once successful, the iPhone will be erased, the existing screen passcode will be removed, and the device will return to its factory settings. You can then go through the setup process again.

If you don't remember the screen passcode of your recovered iPhone, you can also use iTunes to restore the device. This process removes the existing screen lock by erasing the iPhone and returning it to its factory state.
Here are the steps to unlock a stolen iPhone via Recovery Mode:
Step 1. Connect the iPhone to a Computer and Enter Recovery Mode
Connect your iPhone to the computer with a USB cable and open iTunes. Then, put the device into Recovery Mode according to its model:
Step 2. Choose Restore in iTunes
When iTunes detects the iPhone in Recovery Mode, a window will appear with options to update or restore the device. Select "Restore" to begin the process.

Step 3. Wait for the Restore Process to Finish
iTunes will download the appropriate software and restore the iPhone. The process will erase the device, including the forgotten screen passcode.
If you're dealing with an older iPhone running iOS 10.3.2 or iOS 10.3.3 with Siri enabled, you may be able to access the device through a known Siri-based workaround without immediately erasing its data. However, this method relies on vulnerabilities in older iOS versions and does not work on most modern iPhones.
How to unlock an older iPhone using Siri:
Step 1. Press and hold the Home button until Siri appears, then ask Siri, "What time is it?"

Step 2. When Siri displays the current time, tap the "clock" icon.
Step 3. Tap "World Clock", then tap the + icon in the upper-right corner to add another clock.
Step 4. On the Choose a City screen, enter any text in the search box. Tap "Select All" to bring up additional options, then tap "Share".
Step 5. Select "Messages", then enter any text in the To field.
Step 6. Tap return on the keyboard, then tap the "+" icon to create a new contact.
Step 7. Tap add photo, then select "Choose Photo" to open the photo library.
Step 8. Press the "Home" button. If the workaround succeeds, you will be taken to the Home screen and may be able to access the iPhone without entering its passcode.
If you got a second-hand iPhone that might be lost or stolen, you can try the above three methods to unlock the iPhone. To make the task simpler, we recommend trying iOS Unlock, which is an ideal tool for handling the unlocking problem. This tool has an intuitive interface and supports a wide range of iPhone models. Go ahead and install it on your PC to see how it works for you. If you encounter any problems during use, feel free to leave a comment below.
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