Follow these steps to activate your Battle.net game key.
1
Open Battle.net Client
Launch the Battle.net application on your computer.
2
Sign In
Log in to your Blizzard account.
3
Click on Your Account Name
Click on your account name in the top right corner.
4
Select Redeem a Code
Click on Redeem a Code from the dropdown menu.
5
Enter Your Code
Type or paste your product key.
6
Complete Redemption
Click Redeem Code to add the game to your account.
What is Battle.net?
Battle.net is Blizzard Entertainment's online gaming platform for games like World of Warcraft, Diablo, Overwatch, StarCraft, and Hearthstone.