Make Your Writing More Readable With Readability Stats

An image of glasses and text to illustrate the concept of writing readability.

Did you know that in pre-Elizabethan times an average written sentence was 50 words long? Fifty words! Why? I’m guessing that few people read and wrote English in those days. And the ones who did were highly educated, which made it easier for them to read longer sentences.

Things changed after that, although not quickly. Here’s how average sentence length has evolved:

  • Pre-Elizabethan times: 50 words
  • Elizabethan times: 45 words
  • Victorian times: 29 words
  • Early 20th century: 23 words

English professor Lucius Adelno Sherman, from the University of Nebraska, uncovered the first three of these numbers in 1893. He proposed trying to make the written word as similar to the spoken word as possible. Here is what he said: “The oral sentence is clearest because it is the product of millions of daily efforts to be clear and strong. It represents the work of the race for thousands of years in perfecting an effective instrument of communication.” Those are fighting words in the academic world, where some (fortunately not all) seem to hanker for a return to pre-Elizabethan times.

Sherman was also the first person to propose that writing can be analyzed statistically. In fact, before even learning about Sherman, I was already a huge fan of readability statistics. Hidden in every version of MS Word you will find a free readability stats tool that uses the Flesch-Kincaid scale (consult your Help menu for how to activate it). Or, you can go to this no-cost source online.

As you explore readability stats, I urge you to remember that you should aim for a writing level of somewhere between grades 7 and 9. This is not because your readers are stupid or uneducated. It’s because they are pressed for time. Furthermore, you needn’t worry about alienating readers by appearing to “write down” to them. I have run many passages of writing (both my own and others’) through the various indices and discovered that the clearest writing always achieves a low-grade level, even though it doesn’t seem unsophisticated.

But as you work with readability stats, remember that they only measure what computers can easily gauge: sentence length, word length, paragraph length, use of passive voice. This makes them a useful although limited tool to you, the writer. I’ve recently learned, however, that one of the granddaddies of readability, Rudolph Flesch, also created a formula for measuring “human interest” in text. How did I never hear of this before?

“The structural shortcoming of the [Flesch Reading Ease] formula is the fact that it does not always show the high readability of direct, conversational writing,” Flesch admitted  in his scholarly article “A New Readability Yardstick.”

To correct this problem, he developed a new formula designed to test for human interest. Here’s how it works:

Calculate your percentage of personal words: These include nouns with gender (e.g., mom, dad, Jordan, Madison), pronouns with gender (i.e., all pronouns except “it”), and the words “people” and “folks.”

Calculate your percentage of personal sentences: These include all quotations (whether marked with quotation marks or not), sentences addressed directly to the reader (including questions, commands or requests), exclamations, and grammatically incomplete sentences whose meaning the reader must infer from context.

The higher the percentage of personal words and personal sentences, the higher your human-interest score. If you don’t want to do all that counting of words you can ask yourself two simple questions:

  1. Have I quoted enough people?
  2. Am I using lots of concrete words to balance all the abstract ones?

It pleases me to learn that Rudolph Flesch acknowledged the limitations of his initial formula and developed a second one to give us a more nuanced way of improving our own readability. Too bad there’s no handy-dandy software that allows you to run your own stories through this test!

Finally, while we’re talking about readability, let me make one last point about sentence length: The current optimum length for sentences has dropped. It’s now only 18 words. If you ever want to improve your readability the very first thing you should do is check your sentence length.

I did that after writing this column and discovered it had an average of 19 words per sentence. With some quick editing I took it down to 16. ∞

Big thanks for the image up top to Erika Varga on Pixabay.

About Author

Daphne Gray-Grant

Daphne Gray-Grant, principal of The Publication Coach, gives communications advice to corporations and provides support, advice and training to writers around the world. She is author of two bestselling books: 8½ Steps to Writing Faster, Better and Your Happy First Draft. Neither is available in bookstores or on Amazon. If you’re interested in buying go to her website.