A gamma ray burst (GRB) has been observed at redshift z = 8.2.  Ignore everything people say about distance since those numbers are model-dependent.  What you 
can say unquestionably, is that the universe is now z + 1 = 9.2 times larger than it was when this burst occurred.  That means the universe was about 11% it's current size.
This is 
GRB090423A observed by the Swift satellite gamma ray observatory.