Open the Facebook profile you want to check
Look at the profile URL in the browser address bar
If the URL contains numbers, those numbers may be the Facebook ID
If the URL uses a custom username, the numeric ID is not shown directly
View the page source of the profile
Search the source for `profile_id`
Search the source for `entity_id`
Search the source for `userID`
Use Facebook’s Graph API if you have permission and access
Enter the profile username or page URL in a trusted Facebook ID lookup tool
Check the About section of a Facebook Page for page details
Use the mobile app only if the profile settings allow public visibility
Verify the ID by comparing it with the profile name and URL