If you have a Facebook Profile Or Page , That's sure that you have a Unique Numerical ID
Do you want to Know you ID now ?
How To Get Your Facebook Numerical Profile Or Page Id
This method is Very easy
I will give you this example using my facebook profile
for example my facebook profile link : www.facebook.com/abdellah.elmekki
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Step 1 :
replace www. by graph.
So , the link will be graph.facebook.com/abdellah.elmekki
Step 2 :
open it in a new windows
you will have like this
you had see in the bottom the id is : 100008106972336{ "id": "100008106972336", "first_name": "Abdellah", "gender": "male", "last_name": "EL Mekki", "link": "https://www.facebook.com/abdellah.elmekki", "locale": "en_US", "name": "Abdellah EL Mekki", "username": "abdellah.elmekki"}
if you use it like this www.facebook.com/100008106972336 you will be redirected to www.facebook.com/abdellah.elmekki
Enjoy !