Open a Google app or go to a Google service in your browser
Tap or click your profile picture in the top right
Select Sign out or Sign out of all accounts
On a browser, you can also go to Google account settings and choose Sign out
If you want to sign out of one account only, remove that account from the device or browser
On Android, go to Settings, then Accounts, then Google, and remove the account
On iPhone or iPad, open the Google app or Gmail app, tap your profile picture, then manage accounts and remove the account
On Chrome, open your profile icon, then choose Sign out or turn off sync