This is something of a strange one. If you saw Jack Black in the movie 'Gulliver's Travels' (and we appreciate that won't be many of you - the film was a disaster), then you might be laboring under the misapprehension that Black is a giant. Let us put that one to bed for you. He's not. That was all special effects. In fact, we think Black might have been cast in the part as a joke because he's so far from being giant in real life.
Part actor and part rock star, Black has made a career out of playing larger than life characters, and that makes it easy to believe that he's much taller than 5 foot 6, but that's his real height. Everything on top of that is just his charisma. When he's not busy entertaining you on screen, you'll find Black busy writing songs and playing concerts with his friend Kyle Gass in the band Tenacious D.