It really depends on the essay. Some were right at the limit, while others had much less. My rough drafts, though, were always above the word limit. But once I cut them down, the essays were just what I wanted.
I wouldn't worry about it too much; you'll do just fine. Just be versatile and don't blindly adhere to some artificial rule. You might be confronted with different essay requirements, so learn to adapt and be creative. LSE, for instance, allows 3 pages for the personal letter, and it only asks two or three general questions. HEC, for one of its MSc programs, asks a number of specific questions and limits you to 1,000 characters a piece. And that's characters as in letters, not words. Even commas, periods, and spaces count on those essays.
Sorry I couldn't provide you with something more substantial or concrete. But the fact that you're asking these questions suggests that you're mentally in good shape for this challenge. I actually found the essays to be the most enjoyable part of the application process (other than finishing, of course). Good luck!