How to Register TuneFab Audible Converter
Step 1. Install TuneFab Audible Converter
Download and install the latest version of TuneFab Audible Converter on your computer.
Step 2. Activate TuneFab Audible Converter
When you launch the TuneFab Audible Converter, hit "Buy Now" and purchase a license. Or you can go to TuneFab's online site to explore more.
Have a license? Hit "Log in" on the pop-up window. Then click "License Key Login".
Enter your licensed email and license key to log in to TuneFab, and the software will be activated.

How to Convert Audible Books with TuneFab Audible Converter on Windows & Mac
Step 1. Get TuneFab Audible Converter Ready
Launch TuneFab Audible Converter, then enter "Audible" from the interface.

Log in to Audible website with your account.

Step 2. Add Audible Book
After logging in, find the book you want to download. Drag and drop it to the conversion list on the right side, or hit the "Add to the conversion list" button over the audiobook cover art.

Log in to Audible website with your account.

Step 3. Configure Output Preferences
Now expand the conversion list. From the bottom of the main interface, you may change the destination folder to save your converted audiobooks. Choose a desired output format for your Audible books. It provides several options including MP3, M4A, FLAC, AIFF and WAV for exporting. All audiobooks will be converted to high-quality audio files.

Step 4. Download Audible Books to Computer
When all is ready, simply click the "Convert All" button to start converting AAX or AA audiobooks to MP3/M4A/FLAC/WAV/AIFF audio files. You may also convert a specific Audible book to check the output quality. Just click the "Convert" button on the right side of each book title.

To view your output audiobooks, go to the “Finished” tab and click on the file button to find all the converted Audible books. Now you may listen to your Audible purchases on many more media devices.

Advanced Settings
Split Audible Books
TuneFab Audible Converter not only helps you keep all chapter information in your Audible books but also enables you to divide a large audiobook file into multiple parts. Its built-in audiobook splitter lets you conveniently split your AAX or AA audiobooks by chapter and time frame.
Change Output Parameters
Simply select the three-line button from the settings menu in the upper right corner, and you will find all options from the “Preferences” window. Here you may also alter parameters for your output audiobook. Options include sample rate and bitrate.

Edit ID3 Tags
And if you want to edit ID3 tags, click on the edit icon so you may change a new book cover or edit the book title or narrator information before the conversion starts.

Video Tutorial
You can check this video for a detailed guide.