When a child is born, he or she is issued a birth certificate containing the names of the birth mother and father. Because birth certificates are public records, you can run a search for the birth father's name and find all the birth certificates on which his name appears. This can be a helpful tactic in a number of court cases, as well as in doing background checks.
Find the name of the father you want to search. Other information, such as the area in which the birth certificate should be located, is helpful but not required. If you want to do a broad search to find all birth certificates with the father's name on them, then include his full name as the search parameter.
Find a search engine that specialises in public records. There are numerous options on the Internet.
Type in the birth father's name and click search. When the search is complete, you should have a list of birth certificates that contain his name, including his own if the search worked properly.
If the birth father has an extremely common name, or if his name can be spelt different ways, you should search with a careful eye. For instance, John David Smith is likely to have a lot more records out there then Bijoun Lefkowitz.