Flesch Reading Ease and Readability Scores, Explained Simply

Flesch Reading Ease is a readability score from 0 to 100 that tells you how hard your writing is to read. Higher means easier. A score of 70 reads like a magazine article most adults breeze through; a score of 30 reads like a dense legal contract. The formula looks at two things only: how long your sentences are and how many syllables your words carry.

What is Flesch Reading Ease (and what the score means)

Rudolf Flesch published the score in 1948, and it is still baked into Microsoft Word, Google Docs add-ons, and most readability checkers. The output is a single number you can act on.

Here is the rough map most people use:

• 90 to 100: very easy. A 5th grader reads it. Think short children’s books.
• 60 to 70: plain English. Aimed at a 13 to 15 year old. Most web content should land here.
• 30 to 50: difficult. College level. Academic papers and terms-of-service pages.
• 0 to 30: very hard. Legal and technical writing that few people finish.

The number is not a grade. A high score is not “dumb” writing and a low score is not “smart” writing. It measures effort to read, nothing else. Ernest Hemingway scores in the 80s and nobody calls him simple. Insurance policies score near zero and nobody enjoys them.

If your goal is to be understood by a wide audience, aim high. If you write for specialists who expect long technical terms, a lower score is normal and fine.

Flesch Reading Ease vs Flesch-Kincaid Grade Level

People mix these up constantly. They come from the same two inputs but answer different questions.

Flesch Reading Ease gives you the 0 to 100 scale where higher is easier. The Flesch-Kincaid Grade Level converts the same sentence-length and syllable data into a US school grade. A Flesch-Kincaid grade level of 8.0 means an average 8th grader (about 13 years old) can follow it.

So the two move in opposite directions. When Reading Ease goes up, the grade level goes down, because easier text needs less schooling to parse. If a tool reports a Reading Ease of 65 and a grade level of 8, those two numbers agree with each other. They are the same measurement in two costumes.

Which one should you quote? Reading Ease is friendlier for a general readability score you share with a team. The grade level is better when someone asks “what age is this written for,” which is why health and government writing guidelines usually set a target grade instead.

The formula behind the score (sentence length + syllables)

The Flesch Reading Ease formula is:

206.835 minus (1.015 times average words per sentence) minus (84.6 times average syllables per word).

Two levers, and you control both:

• Average words per sentence. Total words divided by total sentences. Long sentences drag the score down fast.
• Average syllables per word. Total syllables divided by total words. Latin-heavy vocabulary (“utilization,” “facilitation”) costs you more than plain words (“use,” “help”).

A quick worked example. Take the sentence “The cat sat on the warm mat.” That is 7 words, one sentence, and 8 syllables. Words per sentence is 7. Syllables per word is 8 divided by 7, about 1.14. Plug it in: 206.835 minus (1.015 times 7) minus (84.6 times 1.14) equals roughly 103. Off the top of the scale, which fits a six-word sentence of tiny words.

Now swap in “The feline positioned itself upon the temperature-elevated floor covering.” Same idea, longer words, and the score collapses into the 20s. Nothing changed except syllable count and sentence length. That is the whole game. Counting syllables by hand gets fiddly, so if you want to check the raw inputs yourself, our guide on how to count syllables walks through the rules and the common traps like silent “e.”

Other readability formulas: Gunning Fog and SMOG

Flesch is not the only readability score. Two others show up often, especially in health and education, and they weight things differently.

SMOG readability formula and Gunning Fog index

The Gunning Fog index estimates the years of formal education a reader needs on first pass. It counts sentence length and the percentage of “complex” words (three or more syllables). A Fog index of 12 means you need about a high-school senior’s reading level. Journalists often target 8 to 10.

The SMOG readability formula (Simple Measure of Gobbledygook) also returns a grade level but leans almost entirely on polysyllable count across a sample of sentences. SMOG is the go-to in healthcare because it was validated for patient materials, and it tends to run a grade or two higher than Fog on the same text, which makes it the cautious choice when the stakes are high.

The practical takeaway: all four (Flesch Reading Ease, Flesch-Kincaid, Gunning Fog, SMOG) reward the same two habits, shorter sentences and shorter words. If you improve for one, you improve for all of them. Do not obsess over which formula a checker uses. Fix the writing and every number moves the right way.

What is a good readability score for your audience

There is no universal “good” score, only a good score for who you are writing for. Match the number to the reader.

• General web content, blogs, marketing: aim for Flesch Reading Ease 60 to 70, or a grade level around 7 to 9. This is the sweet spot for skim-reading on a phone.
• News and consumer email: 65 to 75. Newspapers historically target a low grade level on purpose.
• Health and government notices: many guidelines ask for a 6th to 8th grade level so the widest audience can act on the information.
• Technical docs and academic writing: 30 to 50 is expected. Your readers trade ease for precision, and forcing simple words would strip the meaning.

One caution: readability scores are blind to whether your writing is any good. You can hit a 70 and still be boring, vague, or wrong. Treat the number as a smoke alarm, not a chef. It flags text that is probably too dense; it cannot tell you the ideas are clear.

How to improve readability (practical edits)

Here is how to improve readability without gaming the formula. Every edit below raises the score because it genuinely helps the reader.

Cut sentence length. The single biggest lever. Split any sentence over about 25 words. Find a natural break, add a period, move on. If a sentence has three “and”s, it is probably two or three sentences.

Swap long words for short ones. “Utilize” becomes “use.” “In order to” becomes “to.” “Approximately” becomes “about.” Every syllable you remove nudges the score up and reads more like speech.

Use active voice. “The report was reviewed by the team” (passive, longer) becomes “The team reviewed the report” (active, shorter). Active sentences are almost always tighter.

Break up walls of text. Short paragraphs, bullet lists, and subheadings do not change the raw formula much, but they make the real reading experience easier, which is the point of the score in the first place.

Read it aloud. If you run out of breath before the period, the sentence is too long. Your ear catches what the formula measures.

Do not over-optimize. Chopping every sentence to five words to chase a 90 makes prose choppy and childish. The goal is clear, not simplistic.

How to check readability of your own writing

You have a few easy options. Microsoft Word shows Reading Ease and Flesch-Kincaid grade level in its spelling-and-grammar results once you turn on the readability statistics setting. Google Docs offers add-ons that do the same. Yoast and similar plugins score readability inside WordPress as you draft.

You can also start from the raw inputs. Since the formula depends on total words and total sentences, the fastest first step is an accurate word and sentence count. Paste your draft into our free word counter to get the totals instantly, then you can eyeball your average words per sentence before you even run a full readability check. If that average is climbing past 20, you already know where to cut.

For a fuller picture of how long your content actually is and how that affects reading time, see our related notes on average reading speed and words per page.

FAQ

What is a good Flesch Reading Ease score? For most web writing, 60 to 70 is the target. That maps to a 7th-to-9th grade reading level, which the widest general audience can read comfortably on a phone. Specialist or academic content sits lower (30 to 50) and that is normal.

Is a higher or lower Flesch score better? Higher is easier to read. A score of 100 is very simple; a score near 0 is very hard. “Better” depends on your reader, but for general audiences, higher is what you want.

What is the difference between Flesch Reading Ease and Flesch-Kincaid Grade Level? Same two inputs, different scale. Reading Ease is 0 to 100 where higher means easier. The grade level converts that into a US school grade, so higher grade means harder. They move in opposite directions and always agree with each other.

How do I improve my readability score? Shorten your sentences and use shorter, plainer words. Split anything over 25 words, swap “utilize” for “use,” and prefer active voice. Those three edits raise every readability formula at once.