Readability Checker
Score your writing on Flesch Reading Ease, Flesch-Kincaid, Gunning Fog, SMOG and Coleman-Liau at once, and see which one your text fails.
A readability checker scores how hard a piece of text is to read. This one runs five formulas side by side - Flesch Reading Ease, Flesch-Kincaid Grade Level, Gunning Fog, SMOG and Coleman-Liau - because they weight sentence length and word length differently, and the gap between them tells you whether your problem is long sentences or heavy vocabulary.
Runs entirely in your browser · no signup · nothing is uploaded · updated 2026-08-29
How to use it
- 1.Paste your text.
- 2.Read the Flesch score and the grade level it maps to.
- 3.If it is under 50, shorten sentences before reaching for shorter words.
Frequently asked questions
What Flesch score should I aim for?
60 to 70 for general audiences - plain English, around 8th to 9th grade. Technical documentation naturally lands at 30 to 50 and that is fine for a developer audience.
Is readability a ranking factor?
Not directly. It affects how long people stay and whether they finish, and those behavioural signals do matter.
How is the score calculated?
From average sentence length and average syllables per word. Long sentences hurt the score roughly twice as much as long words do, which is why splitting sentences is the fastest fix.
Should I write for the lowest score possible?
No. Below about grade 6 the writing becomes choppy and condescending. Clarity is the goal, not simplicity.
What Flesch score do popular sites hit?
Most successful consumer writing lands between 60 and 80. Legal and academic writing sits below 30, which is why it is exhausting to read.
Does simplifying language mean dumbing down?
No. It means shorter sentences and fewer Latinate words, not fewer ideas. Technical accuracy and readability are independent - you can explain a complex thing in short sentences.
Why did my score drop when I added a code block?
Syllable counting treats identifiers and URLs as very long words. Score the prose, not the code.
Which single change improves readability most?
Splitting sentences over about 25 words. Sentence length dominates both formulas and is the easiest thing to fix mechanically.
The guide behind this tool
Tools that pair with this one
Text & contentWord Counter
Count words, characters, sentences and paragraphs, with reading time, speaking time and a Flesch readability score. Everything runs in your browser.
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Estimate how long your article takes to read and to speak aloud, so you can put an honest number at the top of the page.
Text & contentKeyword Density Checker
See which words your content actually repeats and at what percentage, with stop words excluded, so you can spot keyword stuffing before publishing.
Text & contentFlesch Reading Ease Calculator
Score any text on the Flesch Reading Ease scale from 0 to 100, see the audience it reads for, and get the sentence length and syllable numbers behind the score.
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