Where can I find someone's date of birth online for free?

Question:

Where can I find someone's date of birth online for free?

I need to find out when someone's birthday is. They were born in the UK and still live in the UK, and they are still alive! I've tried Google but can't seem to find a site that gives me this information - mostly I came across ancestry sites.
Can you help please? I'd be most grateful if you can! Many thanks.

Best Answer - Chosen by Asker: You can do your search for free on www.ancestry.co.uk
there is the 1837-1983 section &1984-2004 there are no indices for the later years though, but you can do the search for free. It only gives the birth year and the quarter they were born in not the actual date, it gives the mums maiden name for those born after 1911, and always gives a volume and page number these are numbers given for on-line orders mainly. Hope this helps good luck.