[MSL]

  I was sure that there is some world population clock and I saw this one www.worldometers.info/world-population/. It's impressive, from my point of view.

 And here -- http://www.worldometers.info/ -- you can see more meters.

[SEO]

7 billion people on 1 page

  That's a very famous website! And here is something noteworthy and related, as well:
7 billion people on 1 page -- http://www.7billionworld.com/