These are instructions on how to Extract KDZ Firmware (file or ROM) using the LG Firmware Extract Tool on Windows Computer.
An .kdz or .dz file is different from a standard zip file. Therefore, you cannot use 7zip or any other zip program to extract it. A developer from the XDA forums has developed a program called LG Firmware Extract Tool to extract the contents of the .kdz or .dz file. It can read and unpack the contents of the .kdz or .dz file, giving you access to individual files (such as system, boot, modem, etc.).
How to Extract Contents of .kdz or .dz File/Firmware
- Download LG Stock Firmware (which contains the kdz or dz firmware) on the Computer. If in case you have already downloaded the firmware on the computer, then SKIP this step.
- Download LG Firmware Extract Tool on the Computer. If in case you have already downloaded the LG Firmware Extract Tool on the computer, then SKIP this step.
- Once you have downloaded the LG Firmware Extract Tool on your computer, Extract it. After extracting the package, you will be able to see the following files:
- Now, Open WindowsLGFirmwareExtract.exe.
Once the tool is launched, you will be able to see the following window:
- Click on the KDZ Open Button and Locate the KDZ Firmware (that you have downloaded in Step#1). If you have a DZ File, then Click on the DZ open Button and locate the Firmware.
- Once you have located the KDZ/DZ Firmware, Double Click on the File to Add it to the Tool.
- Once the KDZ/DZ File is loaded in the Tool, it will automatically display the contents of the KDZ/DZ file.
- Select the File that you want to Extract from the KDZ/DZ File.
- Then Finally, Click on the Extract KDZ button to begin the Extracting process.
- Extracting process may take a few minutes to complete.
- The Extracted File can be found in the Tool Folder (same folder from where you launched the WindowsLGFirmwareExtract.exe tool in Step#3).

Readme Once:
[*] LG Firmware Extract Tool also helps you to extract the contents of .DZ and TOT File.
[*] Know Issue: LG Firmware Extract Tool may not work with all the LG Firmware. As a result, you may sometimes face the Not a KDZ or a TOT File Error while loading the KDZ File. In this situation, try another KDZ File.
[*] LG USB Driver: If you are looking for the Official LG Driver, then head over to the LG USB Driver page.
[*] Credits: Big thanks to bullghost (xda developer) for creating the tool. Without using the LG Firmware Extract Tool, the above tutorial was not possible.