This tool shows a rough chart of the pacing for a given piece of prose. The chapter view is more informative, as it shows how each chapter flows to the next (here 'chapter' can be interchangeable with scene, see note below).

The scores are more than just a simple word count. The calculator also considers how many words are within a given clause, how many clauses are within a given sentence, and how many sentences are within a given paragraph. Each of these additional metrics are weighted differently, to reflect the approximate effect each has on the pacing of a given piece.

You can configure the word-equivalence of clauses and sentences. Higher values will reduce the impact those components have on the final score. You can also configure the delineation between standard-length and high-length sections of prose, as well as the penalty multiplier. You can tune the calculator based on your own writing style (long sentences with multiple clauses or short, punchy sentences), while still getting valuable insight into the relative pacing of each chapter. There is also an option to further penalize sections of dialogue.

You could generate a very similar graph by just counting the words in each chapter. This calculator adds some minor, additional heuristics that, at the end of the day, are reduced to word count equivalents. This calculator makes no promise as to the quality of its results. As always, you are best equipped to determine how your story unravels. There is no rule that can't be broken.