Reading Level Checker
Paste any text and get its reading grade level from seven readability formulas, including Flesch-Kincaid, Gunning Fog and SMOG. Free, instant, runs in your browser, no sign-up.
Your text
Nothing to measure yet. Paste some text above, or try one of the examples.
Every number here comes from counting sentences, words, syllables and letters. None of it knows whether your text makes sense. A grade 6 score on nonsense is still nonsense. Nothing you paste leaves your browser.
How this reading level checker works
Counting sentences, words and syllables
A sentence ends at a full stop, question mark or exclamation mark, or at a line break, so headings and bullet points count as their own sentences. The splitter skips common abbreviations (Mr., Dr., e.g., i.e., etc., a.m.) and single initials like the J. in J. K. Rowling, so they do not chop a sentence in half.
A word is anything between spaces that contains a letter or digit. Hyphenated words count once. A complex word, for the Fog index, has three or more syllables, but proper nouns, hyphenated compounds and words that only reach three syllables through -es, -ed or -ing do not count, which is how Robert Gunning defined it.
How syllables are counted (and where it slips)
There is no dictionary here. Syllables come from rules: count the vowel groups, drop a silent final e (make, whale), keep a consonant plus -le (table, little), drop -es and -ed when they are silent (makes, cooked) but keep them after the sounds that need them (boxes, wanted), and add one back for vowel pairs that split (idea, media, radio).
That gets roughly nine words in ten right. It trips on words like business (counts 3, says 2), quiet and science (counts 1, should be 2). Every free readability checker uses some version of these rules, which is one reason two tools give the same text slightly different scores.
The consensus reading grade level
The big number is the median of six grade estimates: Flesch-Kincaid, Gunning Fog, SMOG, Coleman-Liau, ARI and a grade equivalent of Dale-Chall. A median ignores the one formula that wanders off on a given text, which an average does not. Flesch Reading Ease is left out of the median because it is a 0 to 100 ease score, not a grade.
Highlights and fixes
Highlight mode tints any sentence over 25 words and underlines complex words, with the syllable count on hover. The fixes list is built from your text: the longest sentence, the five longest words, and whichever of sentence count or word length is doing more damage. Those are the two inputs every formula here uses, so those are the only two levers that move the grade.
The seven readability formulas
Flesch Reading Ease
206.835 − 1.015 × (words ÷ sentences) − 84.6 × (syllables ÷ words)Rudolf Flesch, 1948. The only score here where higher means easier. It runs from about 0 to 100 on normal prose (it can spill past both ends): 60 to 70 is plain English, under 30 is the territory of academic journals and insurance policies. Several US states set a minimum Flesch score for insurance policies.
Flesch-Kincaid Grade Level
0.39 × (words ÷ sentences) + 11.8 × (syllables ÷ words) − 15.59J. Peter Kincaid recalculated Flesch for the US Navy in 1975 so it outputs a school grade instead of an ease score. Same two inputs, different weights. It is the grade score Word shows and the one most government style guides quote.
Gunning Fog Index
0.4 × [(words ÷ sentences) + 100 × (complex words ÷ words)]Robert Gunning, 1952. A complex word has three or more syllables, not counting proper nouns, compounds or -es, -ed and -ing endings. The result is the years of schooling a reader needs to follow the text on first read. Gunning suggested staying under 12 for anything meant for a wide audience.
SMOG Index
1.0430 × √(polysyllables × 30 ÷ sentences) + 3.1291G. Harry McLaughlin, 1969. Counts every word of three or more syllables, proper nouns included. It was built on 30-sentence samples and gives the grade at which a reader gets full comprehension, so it runs a grade or two higher than Flesch-Kincaid. Health writers like it for that reason. Under 30 sentences, the result here is an estimate.
Coleman-Liau Index
0.0588 × L − 0.296 × S − 15.8 (L = letters per 100 words, S = sentences per 100 words)Meri Coleman and T. L. Liau, 1975. Counts letters instead of syllables, which was easier for machines reading punched text. It rewards short words even when they are rare.
Automated Readability Index
4.71 × (characters ÷ words) + 0.5 × (words ÷ sentences) − 21.43Built for the US Air Force in 1967 to run on electric typewriters that counted keystrokes. Like Coleman-Liau it uses characters (letters and digits) per word rather than syllables.
Dale-Chall (approximate)
0.1579 × (% difficult words) + 0.0496 × (words ÷ sentences), + 3.6365 if difficult words > 5%Edgar Dale and Jeanne Chall, 1948, revised 1995. A difficult word is one not on a list of about 3,000 words most fourth graders know. This page embeds only the 450 or so most common of those, plus their regular endings, and treats other short one-syllable words as familiar. Close on everyday text, less reliable on anything unusual, hence the label. A raw score of 4.9 or less is fourth grade or below; 10 or more is college graduate.
Reading levels in practice
Why readability formulas disagree
They measure different things. Flesch-Kincaid and SMOG lean on syllables. Coleman-Liau and ARI count letters, so a text full of short but rare words ("ergo", "tort") looks easy to them. Gunning Fog punishes every three-syllable word equally, so technical writing with words like computer and important gets hit hard. Dale-Chall asks whether a word is familiar at all, which is closer to how readers actually struggle.
They were also calibrated on different material: Navy training manuals for Flesch-Kincaid and ARI, children's books for Dale-Chall, adult prose for SMOG. A spread of two or three grades between them is normal. That is why the checker reports a median rather than picking a favourite.
What grade level to aim for
| Writing for | Aim for |
|---|---|
| Children's books, early readers | Grade 1–4 |
| Health information, public notices, forms | Grade 6–8 |
| General public, websites, email | Grade 7–9 |
| Newspapers and magazines | Grade 8–10 |
| Business reports, trade press | Grade 10–12 |
| Academic papers, legal and technical writing | Grade 13+ |
Writing below your reader's level costs nothing. Clever readers do not mind plain sentences; tired, rushed or second-language readers need them.
Lexile and AR levels: why this checker cannot give you one
A Lexile measure (like 850L) comes from MetaMetrics' own formula, which weighs sentence length against how often each word appears in their private corpus of hundreds of millions of words. The formula and word frequencies are not published, so nobody outside MetaMetrics can compute a true Lexile. Their free Lexile Text Analyzer on the Lexile Hub is the place to get one.
AR levels (like 4.5) come from Renaissance's ATOS formula, which uses sentence length, word length and a graded vocabulary list of its own. Renaissance runs a free ATOS analyzer for that.
As a rough bridge, the US CCSS text complexity bands put grades 4–5 at about 740L–1010L, grades 6–8 at 925L–1185L and grades 9–10 at 1050L–1335L. Treat any grade to Lexile conversion as a ballpark, not a match.
How to lower your reading level
- Split long sentences. Any sentence over 25 words usually hides two ideas. Find the "and", "which" or comma where they join and put a full stop there.
- Swap long words for short ones. Use for utilize, help for assist, about for approximately, start for commence.
- Cut nominalizations. "Make a decision" becomes "decide". Verbs are shorter than the nouns built from them.
- Use active voice. Passive sentences run longer and hide who does what. The passive voice checker finds them.
- Keep the jargon you need, define it once. A necessary technical word raises the grade. Keep it, explain it, move on.
Rewrite for the reader, then re-check. Chasing the number by chopping every sentence into four words gives you a low grade and a text that reads like a ransom note.
Related tools
- Text Simplifier rewrites dense text into shorter, plainer sentences.
- Passive Voice Checker highlights passive constructions and weasel words.
- Legalese Translator turns contract language into plain English.
- Tone Checker tells you how formal, warm or tense a message reads.
Frequently asked questions
What is a reading level checker?
A reading level checker runs your text through readability formulas that estimate how many years of school a reader needs to follow it. This one uses seven formulas, including Flesch-Kincaid, Gunning Fog, SMOG and Coleman-Liau, and reports the median as a single US grade level. The formulas only count sentence length and word length, so they measure how hard a text is to read, not whether it is correct or well argued.
How do I check the reading grade level of my text?
Paste the text into the box at the top of this page. The consensus grade, all seven formula scores and the text statistics update as you type. Paste at least 100 words, ideally a few hundred, because one long sentence can swing the score of a short passage by several grades.
Is this reading level checker free?
Yes. It is free with no sign-up, no word limit and no upload. The formulas run in your browser, so the text you paste never leaves your device.
How is the Flesch-Kincaid grade level calculated?
Flesch-Kincaid Grade Level = 0.39 × (words per sentence) + 11.8 × (syllables per word) − 15.59. A text averaging 15 words per sentence and 1.5 syllables per word scores about grade 8. The result maps to a US school grade, so 8.0 means an average eighth grader should follow it.
What is a good Flesch Reading Ease score?
For most writing aimed at adults, 60 to 70 is the target: that is plain English at roughly 8th to 9th grade. Above 80 is easy enough for children. Below 30 is very difficult and typical of academic papers and legal documents. Higher is always easier on this scale.
How do I calculate the Gunning Fog index?
Add the average sentence length to the percentage of complex words, then multiply by 0.4. Complex words have three or more syllables, not counting proper nouns, hyphenated compounds, or words that only get there through -es, -ed or -ing. A fog index of 12 means a reader needs about 12 years of school; most popular writing sits between 8 and 12.
Can this reading level checker give a Lexile or AR level?
No. Lexile measures come from a proprietary MetaMetrics formula built on word frequencies from their private text corpus, and AR levels come from Renaissance's ATOS formula and its own vocabulary list. Neither is published, so any site that claims to compute them for free is guessing. Use the free Lexile Text Analyzer or the ATOS analyzer from Renaissance for official numbers.
How do I check reading level in Microsoft Word?
Go to File, Options, Proofing, and tick Check grammar with spelling and Show readability statistics. On a Mac it is Word, Preferences, Spelling and Grammar. Run a spelling and grammar check and a box appears at the end with Flesch Reading Ease and Flesch-Kincaid Grade Level. Word only gives those two, so paste the text here if you want Fog, SMOG and the rest.
Can I use this as a reading level checker for books?
Yes, with samples. Paste two or three passages of a few hundred words from the start, middle and end of the book, check each one, and take the middle grade. Dialogue-heavy chapters score easier than descriptive ones, so one sample alone can mislead. For school book levels like Lexile or AR, look the title up in the publisher or library database.
Why does my essay get a different reading level on different checkers?
Each checker counts syllables and sentences with its own rules, and each formula weighs them differently. One tool may treat a heading as a sentence and another may glue it to the next paragraph, and syllable counters disagree on words like business or every. A difference of one or two grades between tools, or between formulas, is normal. Compare drafts on the same checker rather than comparing tools.