You don’t want your writing going way over peoples’ heads. Well, unless you enjoy the chaos of leaving people scratching their heads. But it’s better to keep your writing at a level most people will have no trouble reading. The Readability Test Tool is your friend in determining readability.
You can enter a URL and receive scores by the page, or type/paste in your piece word for word and see just how readable it is. You’ll get a variety of test scores based on multiple readability indices. Plus, you’ll get a breakdown of your text statistics.