The Readability Scorer tells you, in plain numbers, how hard your writing is to read. Paste a paragraph, an article, an email or a whole blog post and it instantly returns the two best-known readability metrics — Flesch Reading Ease and the Flesch-Kincaid grade level — alongside the raw statistics that drive them: the number of sentences, words, syllables and characters, plus averages like words per sentence and syllables per word. It also reports the Gunning Fog and SMOG indices as second opinions, and estimates how long the text takes to read silently and to speak aloud. Everything runs in your browser, so confidential drafts never leave your machine, and your text is saved locally so it survives a refresh.
Readability scores matter because most readers skim, and dense prose loses them. Search engines, email clients and content teams increasingly check reading level, and accessibility guidelines for public-sector and health content often require grade 8 or below. Knowing your score turns a vague feeling that a sentence is “too heavy” into a measurable target you can actually hit.
How it works
The tool parses your text into sentences and words, then estimates the syllables in every word using a vowel-group heuristic with the usual English adjustments. From those counts it computes the average words per sentence and average syllables per word — the two levers behind almost every readability formula. Flesch Reading Ease is 206.835 − 1.015 × (words/sentence) − 84.6 × (syllables/word), producing a 0 to 100 score where higher is easier. The Flesch-Kincaid grade rearranges the same inputs into a US school grade with 0.39 × (words/sentence) + 11.8 × (syllables/word) − 15.59. Long sentences and long words push both metrics toward “difficult”. The colour band next to the score names the target audience, and a hardest-sentences panel ranks your most difficult sentences so you know exactly what to cut first.
Example
Take this sentence: “The implementation of the aforementioned methodology necessitates a comprehensive reconceptualisation of stakeholder engagement.” It is one sentence of 14 words, but those words are long and multi-syllabic, so it scores a Flesch Reading Ease near 10 and a Flesch-Kincaid grade above 18 — postgraduate territory. Rewrite it as “Doing this means rethinking how we work with the people involved.” and the ease score jumps above 70 with a grade around 6. Same meaning, far more readable. The scorer lets you make that change and watch the numbers move in real time.
Tips for raising your score
Shorten sentences first — splitting one 30-word sentence into two usually moves the grade level down a full point. Swap long words for short ones where you can: use instead of utilise, help instead of facilitate. Read your draft aloud; anywhere you run out of breath is a sentence worth trimming. Then paste the revision back in and confirm the gain.