Instagram User ID is the numeric User ID which you need in some important works like getting followers, identifying any profile if there are too many profiles, etc.
You do not need anything except Instagram Username. If you know the username of any profile then you can easily find the user id of any profile.
Instagram User ID is very useful, it is needed in many works like:
How To Use Techyhit Instagram User ID Finder?
BUGthen please contact to admin via Create a Support Ticket!".