Facebook ID is also known as the fb login id is a unique number assigned to all the users across the globe. It is similar to a roll number in class, or you can say similar to a contact number of a person every user is assigned a unique 15 digits’ Facebook ID number which counts to 100 trillion numbers.
How to Find Facebook ID number manually? If you want to find your FB ID (can be user profile or page or group) manually, please follow the below instructions. Using Computer. Go to https://www.facebook.com and login to your FB account. Click your name (along with your profile picture) in the left hand side of Home button or simple go to this link