From the Combine:

Clemson WR Sammy Watkins measured 6-foot 3/4 and 211 pounds at Friday's NFL Combine weigh-in.
He was listed at 6-foot-1, 205 at Clemson. So the size isn't a detriment. Watkins is a highly explosive, NFL-ready route runner with rare ability to blow past defensive backs in and out of breaks and create separation very early in pass patterns. He will be the first wide receiver chosen in May's draft.