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Uses the standard Flesch Reading Ease and Flesch-Kincaid Grade Level formulas, based on a heuristic syllable count (the same approach used by most readability tools). Treat scores as a useful estimate, not an exact measurement.
Check the Readability of Your Text
The Tools Kit’s free Readability Checker tells you how easy your writing is to read. Paste a paragraph, article, or essay and it calculates the Flesch Reading Ease score and the Flesch-Kincaid Grade Level, shows your average words per sentence and number of complex words, and lists sentences longer than 25 words (up to 10 at a time) so you know where to simplify.
Scores update live as you type, and the analysis runs entirely in your browser, so nothing you paste is uploaded. It is a quick way to check the reading level of a blog post, a school assignment, or a customer email before anyone else reads it.
How to Use the Readability Checker
- 1
Paste your text
Paste a paragraph, blog post, email, or essay into the text box, or type directly into it.
- 2
Read your scores
The Flesch Reading Ease score, Flesch-Kincaid Grade Level, average words per sentence, and complex-word count appear instantly and update as you type.
- 3
Review long sentences
Sentences over 25 words are listed below the scores with their word counts (up to 10 at a time), as candidates for splitting.
- 4
Edit and recheck
Shorten long sentences or swap long words for simpler ones in the box, and watch the score change live.
Below the scores you will also see the total sentence, word, and syllable counts. If you need a detailed word and character breakdown for a length limit, the word counter or character counter is the better fit.
Flesch Reading Ease Score Chart
The Flesch Reading Ease score runs from 0 to 100. Higher scores mean easier text. The checker labels your score using the standard bands below.
| Score | Label | Approximate reading level |
|---|---|---|
| 90-100 | Very easy | 5th grade |
| 80-89.9 | Easy | 6th grade |
| 70-79.9 | Fairly easy | 7th grade |
| 60-69.9 | Standard | 8th-9th grade |
| 50-59.9 | Fairly difficult | 10th-12th grade |
| 30-49.9 | Difficult | College |
| 0-29.9 | Very difficult | College graduate |
Most general web content, news writing, and business email lands comfortably in the 60-70 “Standard” band. Academic papers and legal or technical documents often score between 30 and 50.
Readability Formulas, With Worked Examples
Both scores use the same two inputs: average sentence length (words per sentence) and average word length (syllables per word).
- Flesch Reading Ease = 206.835 − 1.015 × (words ÷ sentences) − 84.6 × (syllables ÷ words)
- Flesch-Kincaid Grade Level = 0.39 × (words ÷ sentences) + 11.8 × (syllables ÷ words) − 15.59
Example 1: text averaging 15 words per sentence and 1.5 syllables per word scores 206.835 − 15.225 − 126.9 = 64.7 on Reading Ease (“Standard”), and 5.85 + 17.7 − 15.59 = grade 8.0.
Example 2: lengthen that to 20 words per sentence at 1.6 syllables per word, and Reading Ease falls to 206.835 − 20.3 − 135.36 = 51.2 (“Fairly difficult”), while the grade level climbs to 7.8 + 18.88 − 15.59 = 11.1. A few extra words per sentence and slightly longer words cost about 13.5 points.
The raw Flesch formula can go above 100 or below 0, so the checker caps Reading Ease between 0 and 100. The grade level is never shown below 0 but has no upper limit, so extremely dense text can return a grade well above 12.
How to Improve Your Readability Score
Because the formulas only look at sentence length and syllables, there are two levers. First, split long sentences: start with the ones the checker lists as over 25 words, since each split lowers your average words per sentence. Second, replace long words with shorter ones where the meaning stays the same, such as “use” for “utilize” or “help” for “facilitate”. The complex-word count shows how many words of three or more syllables remain.
If a passage needs a full rewrite rather than small edits, try the paraphrasing tool to reword it, or cut it down with the text summarizer, then paste the result back here to compare scores. A readability score does not catch grammar errors, so run the final draft through the grammar checker as well.
Limits of Readability Scores
Syllables are estimated, not looked up in a dictionary. The checker counts vowel groups, treats words of three letters or fewer as one syllable, and strips endings like a silent e or -ed, so some words, such as past-tense verbs ending in -ted, are undercounted. Sentences are split at periods, question marks, and exclamation points, which means abbreviations like “Dr.” can start a new sentence. Only letters A to Z count as words, so numbers are ignored and the tool is meant for English text.
A good score also does not guarantee clear writing: a short sentence packed with jargon can still confuse readers. Use the score to spot problem areas, then judge the text yourself.
Common uses
- Checking the reading level of a blog post or landing page before publishing
- Simplifying technical documentation, policies, or instructions for a general audience
- Hitting a plain-language or style-guide readability target
- Comparing two drafts to confirm a rewrite really made the text easier to read
- Reviewing a school essay or report alongside the other writing tools
For students, the essay checker pairs well with this tool, and you can find more writing utilities in our writing and citation tools.
Readability terms explained
| Term | What it means here |
|---|---|
| Flesch Reading Ease | A 0-100 score from Rudolf Flesch’s formula; higher means easier to read |
| Flesch-Kincaid Grade Level | The US school grade a reader would need to follow the text comfortably |
| Words per sentence | Total words divided by total sentences; the sentence-length half of both formulas |
| Syllables per word | Total syllables divided by total words; the word-length half of both formulas |
| Complex word | A word of three or more syllables, as counted by the tool’s syllable estimate |
| Long sentence | A sentence of more than 25 words, which the tool lists for possible splitting |
Frequently Asked Questions
A readability checker measures how easy a piece of text is to read using formulas based on sentence length and word length. This one reports the Flesch Reading Ease score, the Flesch-Kincaid Grade Level, average words per sentence and complex words, and lists sentences over 25 words.
A score of 60 to 70 is "Standard", readable by most adults at about an 8th to 9th grade level, and is a common target for web pages and business writing. Scores of 80 and above suit very casual or young audiences, while 30 to 50 is typical of academic and technical writing.
Reading Ease = 206.835 - 1.015 × (words ÷ sentences) - 84.6 × (syllables ÷ words). Text averaging 15 words per sentence and 1.5 syllables per word scores about 64.7. The checker caps the result between 0 and 100.
Grade Level = 0.39 × (words ÷ sentences) + 11.8 × (syllables ÷ words) - 15.59. Text averaging 15 words per sentence and 1.5 syllables per word comes out at about grade 8. The checker never shows a grade below 0, but there is no upper cap.
For a general audience, aim for roughly an 8th to 9th grade level, which is a Reading Ease score of about 60 to 70. Content for specialists can sit higher, but shorter sentences and plainer words help almost every reader.
Shorten your sentences and use shorter words. Split any sentence the checker flags as over 25 words, replace three-syllable words with simpler ones where the meaning survives, and recheck. Both changes raise Reading Ease and lower the grade level.
It is an estimate. The tool counts vowel groups, treats words of three letters or fewer as one syllable, and strips endings such as a silent e or -ed. That works for most everyday English words but can miscount some, such as past-tense verbs ending in -ted or -ded, so treat scores as a guide rather than an exact measurement.
The Flesch formula can produce values above 100 for very short sentences made of one-syllable words, and the checker caps those at 100. A very short sample, or text made mostly of numbers, which are not counted as words, can also land at 100, so test a full paragraph or more.
No. The Flesch formulas and the syllable counter are designed for English, and only the letters A to Z are counted as words, so accented letters and non-Latin scripts are not scored correctly.
No. The analysis runs entirely in your browser, so the text you paste is not sent to a server. The checker is free, with no signup.
Reviewed by Raja Jahangir · Last reviewed: October 7, 2026
How do you check the readability of your text?
To check readability, paste the text and the Flesch Reading Ease score, Flesch-Kincaid grade level, average words per sentence, and complex-word count update as you type. Reading Ease is 206.835 minus 1.015 times words per sentence minus 84.6 times syllables per word, so 15-word sentences averaging 1.5 syllables score about 64.7. Sentences over 25 words are flagged.
What is a good Flesch Reading Ease score?
A Flesch Reading Ease score of 60 to 70 is "Standard", readable by most adults at an 8th to 9th grade level, and is the usual target for web copy and business writing. Scores above 80 suit children's or very casual content; 30 to 50 is typical of academic papers. Shorter sentences and simpler words raise the score.