Writing that feels clear to the person who wrote it can land very differently with a reader, which is why this readability score checker hands you an outside opinion. Five established formulas run on the same passage, from Flesch Reading Ease to SMOG, with a plain verdict on your audience.
Paste a passage and all five indices recalculate with every keystroke.
Flesch Reading Ease = 206.835 − 1.015 × (words ÷ sentences) − 84.6 × (syllables ÷ words)
Flesch-Kincaid Grade = 0.39 × (words ÷ sentences) + 11.8 × (syllables ÷ words) − 15.59
Gunning Fog = 0.4 × ((words ÷ sentences) + 100 × (complex words ÷ words))
Coleman-Liau = 0.0588L − 0.296S − 15.8, where L is letters per 100 words and S is sentences per 100 words
SMOG = 1.0430 × √(complex words × 30 ÷ sentences) + 3.1291
Every readability formula in common use rests on the same two observations: long sentences are harder to hold in working memory, and long words tend to be rarer, more abstract and more specialised. Feed a passage in and the formulas convert those two signals into a single number that estimates how much effort a reader has to spend.
None of them can judge whether an argument is logical, whether a metaphor lands or whether a chapter is boring. A passage of elegant nonsense will score beautifully. What they do reliably catch is the drift towards dense, clause-heavy prose that creeps into nonfiction, academic writing and business books almost by default.
Running several formulas together is far more useful than trusting one. Flesch and Flesch-Kincaid weight syllables heavily, Coleman-Liau uses letters and ignores syllables entirely, and Gunning Fog and SMOG focus on the proportion of long words. When they agree, the reading is solid. When they scatter, your passage usually has an unusual feature worth looking at.
The checker uses a vowel-group heuristic with silent-e handling: adjacent vowels form a single group, a trailing silent e is stripped before counting, and consonant-plus-le endings get their syllable back. It is accurate for the overwhelming majority of English words.
A Flesch Reading Ease score between 60 and 70 puts you in plain English, the range most trade nonfiction and commercial fiction occupies. Falling below 50 across a whole chapter is a signal, not a verdict, but it usually rewards a second pass.
A grade eight reading level does not mean writing for children. It means an adult can absorb your point without rereading, which is exactly what most readers want after a long day. Some of the most respected nonfiction in print scores there.
Formulas were designed for passages of a few hundred words. Score a single paragraph and one unusually long sentence can move the result by ten points, so test a full section rather than a snippet whenever you can.
Cramped measure, tight leading and inconsistent headings undo good prose. Our nonfiction typesetting gives your argument room to breathe in print and on screen.
What each score range means, and the kind of writing that typically lands there.
| Score | Difficulty | Who reads it comfortably | Typical example |
|---|---|---|---|
| 90 - 100 | Very easy | Confident readers of about 10 | Early chapter books, simple instructions |
| 80 - 89 | Easy | Readers of 11 to 12 | Middle grade fiction, popular magazines |
| 70 - 79 | Fairly easy | Most teenage readers | Young adult novels, tabloid features |
| 60 - 69 | Plain English | The general adult reader | Commercial fiction, trade nonfiction |
| 50 - 59 | Fairly hard | Comfortable adult readers | Broadsheet features, literary fiction |
| 30 - 49 | Difficult | University level | Academic articles, technical manuals |
| 0 - 29 | Very difficult | Specialists only | Legal contracts, research papers |
For commercial fiction and trade nonfiction, a Flesch Reading Ease around 60 to 70 with a grade level near 8 is the comfortable target. Literary fiction often sits lower by design, and technical or academic titles lower still because their readers expect the vocabulary.
Each one weights different features. Coleman-Liau counts letters and never looks at syllables, so it handles unusual names better. Gunning Fog and SMOG hinge on the share of three-syllable words. Wide disagreement usually points to something distinctive, such as heavy dialogue or a burst of proper nouns.
No. Chasing a number produces choppy, artificial prose full of sentences that all run the same length. Use the score as a diagnostic that tells you where to look, then fix the passage by rewriting for sense rather than for arithmetic.
The vowel-group method with silent-e handling agrees with a dictionary for roughly nineteen out of twenty ordinary English words. Invented names, foreign borrowings and unusual compounds are where it slips, which matters little once you are scoring a few hundred words.
Considerably. Dialogue is built from short sentences and short words, so heavy dialogue pushes reading ease up and grade level down. Score narrative passages separately from dialogue-driven ones if you want a fair picture of your descriptive writing.
They matter for the same reason they matter anywhere: readers abandon books that feel like work. Nobody sees your score, but they feel its effects in the sample pages, which is exactly where a browsing reader decides whether to buy.
They use the same two inputs but scale them differently. Reading Ease produces a number from roughly 0 to 100 where higher means easier, while Flesch-Kincaid converts the same measurements into a United States school grade, where higher means harder.
Yes, and it is mostly structural. Split sentences that carry more than one idea, move the subject and verb closer to the start, cut nominalised verbs such as make an assessment, and keep your technical terms while trimming the ordinary words around them.
Readability is not only about words. Line length, leading, heading hierarchy and where a list breaks all change how quickly a reader absorbs a page. We typeset nonfiction so the structure works as hard as the sentences do.
See Nonfiction Formatting