How do I log out of (lock) my wallet?

Remember: MetaMask isn't like a traditional website, where you're logging in to a remote server. Rather, MetaMask stores your Secret Recovery Phrase, private keys, and a certain amount of information about how you use MetaMask (the 'state logs') on your local device, so that whenever you want to carry out an operation on a blockchain, your SRP and private keys are ready to be used.

In this sense, you don't log out of MetaMask, but you can lock the application, so that you'll have to re-enter your password or biometrics to log back in.

• Extension
• Mobile

Click the three vertical dots in the top right of your wallet, and then select 'Lock MetaMask' from the dropdown menu:

You can also set an auto-lock, which you can find in Settings > Advanced:

Here you can set a timer in minutes after which the wallet will be locked.

You can also add an extra layer of security by adding a hardware wallet. Refer to this article on hardware wallet integration.

To manually lock the app, tap the gear icon in the tab to access settings, and then scroll to the bottom. Tapping 'Lock' will prompt a confirmation message:

You can also add an extra layer of security by adding a hardware wallet. Refer to this article on hardware wallet integration.