How To Root Samsung Galaxy S3

1. Download and install the Samsung Galaxy S3 Toolkit. 

2. Run the Toolkit. In the first step you’ll need to select a matching phone model and build. 

The build does not need to match exactly, you can choose the next one up or down so long as you are running the same version of Android. For example, I had Android 4.0.4 with build BLG8, so I went option 4 (BLG9).

3. Connect the S3 via USB in MTP (media) mode.

4. This is the main Toolkit menu. If you already have the USB drivers the serial number will be shown at the top under ‘ADB MODE’. If not, disconnect your handset and select option 1, following the steps to install the drivers.

[Driver troubleshooting tips: uninstall Samsung Kies, reboot your computer after installation, ensure USB debugging is enabled]

5. Once the phone is correctly detected, select option 2.

6. In the next menu choose option 3. This will give you the complete package: rooted boot image, Superuser, BusyBox and ClockworkMod Recovery.

7. Wait until it prompts you to continue then type yes to proceed.

8. Your handset will reboot into Download Mode. Don’t mess with it. Another window will pop open on your computer, this is Odin. Say hello. Keep Odin and the Toolkit side by side so you can follow the instructions.

9. As it instructs, click the PDA button on Odin and locate the .tar file for your handset. Ensure that only Auto Reboot and F.Reset Time are ticked then click Start.

10. Let Odin do its thing. The Toolkit will tell you to exit once ‘RESET’ or ‘PASS’ appear in the top left corner, but the exit button stays greyed out. I exited the old fashioned way by clicking the X close button.

11. The Toolkit will detect that Odin has closed and continue by itself. Just wait while it installs Busybox and CWM and runs through the checks. Your phone will reset and the Toolkit will indicate when it’s finished.

12. You should now have root.

If you reboot your handset into Recovery Mode by switching it off then back on while holding power, volume down and home you’ll get access to CWM Recovery, through which you can save a full backup of the phone (recommended) and install ROMs and other goodies.