Before Grammarly, Rudolf Flesch Was a Writer’s Best Friend

Jen McGahan
Oct 6 · 5 min read

Why the F-K and Readability scores still matter for Medium writers

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Photo by Jerry Wang on Unsplash

Two generations ago, Rudolf Flesch wrote a book that changed the way children learned to read.

Why Johnny Can’t Read explained to educators in 1955 how to teach reading using phonics, rather than the whole-word “see and say” method used in primers like Dick and Jane. At the back of the book, Flesch included 72 lists of words that young children should be able to read, although, at the time, no books contained only those simple words.

The director of Houghton Mifflin’s education division, William Spaulding, set out to change that. He asked Ted Geisel (a.k.a. Dr. Suess) to dinner and challenged him to write “a story that first-graders can’t put down.”

Using 236 words from a list of 348 words, Geisel created The Cat in the Hat. It was a hit, first with parents, then with schools. Since its publication in 1957, the sensational book has over 16 million copies in print.

Rudolph Flesch, the author of the book that started the easy-reading craze, also created a score to analyze the readability of texts. As a writer, you should be aware of the test that helps you write for your intended audience, of any reading ability. You don’t need to worry about the algorithm itself, but it helps to know that you can adjust certain words in your text to obtain the desired score for your intended audience.

How easy should your text be to read?

The way Flesch designed the test, it takes into account the totals of words, sentences, and the syllables of words, which you can measure to analyze reading ease. On a scale of 0–100, the more difficult texts range higher, while the easy-to-read texts are lower. For example, a fifth grader is comfortable with texts with scores of around 90; a college thesis would have a score of around 20.

When I’m writing copy, I try for a score between 80 and 90, because consumer readability is at around the 6th-grade level.

Copywriters should take special note of the reading ease scale. Please don’t make the mistake of assuming your audience is smarter than it is. I’m sure they’re smart, but even someone purchasing accounting software, hard drives, telescope lenses, or something high-tech, responds best to simple “human” text when making a purchasing decision.

What grade level are your writing to?

Have you ever wondered how Grammarly does what it does? It combines several readability algorithms and churns out the results in a satisfying way.

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Courtesy of the author (and Grammarly)

One of the tried and true tests for readability, however, still stands on its own and remains valuable for writers. The F-K score estimates the grade level required to understand your text.

Flesch and his colleague Peter Kincaid designed this test for the U.S. Navy to use to standardize its training manuals. To ensure that people understood the texts, they needed to be sure they were written to a maximum of a 9th-grade level.

Jumping on the bandwagon, many states instituted rules for insurance companies to standardize policies at no higher than a 9th-grade level. Still, economic and legal lingo often almost feels like entrapment. Privacy policies on websites and sign-in wrap contracts, contracts that the user implicitly agrees to by using a website, are often very difficult to read. Consumer advocates have urged companies to do better. (I just checked Facebook’s terms of service and its privacy policy, and both are considered to be fairly easy to read by an 8th grader.)

And sometimes, difficult texts hide the most difficult truths. If your purpose is to hide something, pull out the big guns and write to a college-graduate level reader. Use lots of polysyllabic words and long sentences. Whatever you’re trying to disguise will very well get lost in the gobbledygook.

Say you’re explaining complicated economic theory or scientific journalism. Should you lean into complicated words and lingo? Not if you want to be understood!

Before making the argument that your subject is naturally complicated, and therefore requires a higher level of writing, take this in. Richard Feynman’s classic Lectures on Physics has a reading level of grade 8. If a Nobel Prize-winning physicist can explain Heisenberg’s Uncertainty Principle to 8th graders, you can probably simplify your writing, too.

Tips for making your text easy to read

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This story's stats, according to WebFX. Image courtesy of the author.

You should too. Here’s how to edit for lower grade levels.

  • Use short words.
  • Break long sentences into smaller ones.
  • Make sure transitions are clear. (Reading aloud helps.)
  • Use shorter paragraphs.

I figure some of my favorite literature is geared toward 7th and 8th-graders; my Medium stories should be, too. I hope this helps you write for simplicity and clarity. Easy reading doesn’t have to be Dr. Suess-like. Just stay human, write as you talk, and you’ll do just fine.

By the way, The Cat in the Hat has a Flesch- Kincaid grade level of less than one. This story’s F-K score is 7.4, meaning it’s suited for 7th-graders. Right where I want to be.

I like words, and writing about them. If you want to know the 5 most powerful words in the English language, you can download them here.

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Jen McGahan

Written by

Curious mom, writer, & lymphatic massage therapist. I teach a persuasive writing course, too. Start here: https://www.jenmcgahan.com/power-words

Portals Pub

Fearless learning, disparate connections, and honest writing

Jen McGahan

Written by

Curious mom, writer, & lymphatic massage therapist. I teach a persuasive writing course, too. Start here: https://www.jenmcgahan.com/power-words

Portals Pub

Fearless learning, disparate connections, and honest writing

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