You can find your Account ID and Application Key when you sign into your account and navigate to the Buckets page. On this page, click on the link that reads 'Show Account ID & Application Key".
You'll then see a window like the one below:
IMPORTANT: When you click to Create Application Key, please save this key in a safe location that you can refer to later. Once you close this window, the current Application Key will not display again. You would need to create another Application Key if you lose the first one. The new key that you create will invalidate the old one. All the places where you have specified the Application Key will need to be updated, including tools like Cyberduck, Synology CloudSync, and the B2 command line tool.
You can now use your Account ID and Application key to use any of our integrated products or to authorize the B2 Command Line tool.
If you need help with installing the Command Line tool, please refer to our documentation page here. Once the Command Line tool is installed, you will need to authorize your B2 account in order to make other B2 calls. First, you'll need to take note of your B2 Account ID and Application Key.
Next, open up your Terminal/Command Prompt on your computer, type in 'b2 authorize_account', and Click Enter. Input your Account ID, click Enter, then your Application Key and click Enter.
Once completed, you will be able to use all of the command line calls for B2. You can run 'b2 help' for more information about each call in the Command line.