Readability Checker

{{ targetBadge }} {{ readingEaseDisplay }} {{ wordCountDisplay }} {{ averageSentenceDisplay }} {{ signalCountDisplay }} {{ gradeSpreadDisplay }}

Text:

Paste a draft, article, notice, email, or drop one plain TXT file.

Drop TXT onto the textarea.

Reader target:

Pick the audience you are trying to keep the passage readable for.

Sentence splitting:

Use line-aware mode for bullet lists, notes, and copied slide text.

Long sentence threshold:

Lower values catch more sentences for rewrite review.

words

Complex word threshold:

Most readability formulas treat 3 or more syllables as complex.

syllables

Long word threshold:

Enter 6-24 letters to tune long-word flags.

letters

Export label:

Optional label such as Homepage hero copy or Benefits email v2.

Metric	Value	Reading	Copy
{{ row.metric }}	{{ row.value }}	{{ row.reading }}

Formula	Score	Band	Basis	Copy
{{ row.name }}	{{ row.score }}	{{ row.band }}	{{ row.basis }}

Signal	Current	Status	Revision cue	Copy
{{ row.signal }}	{{ row.current }}	{{ row.status }}	{{ row.cue }}

#	Words	Flags	Sentence	Copy
{{ row.index }}	{{ row.words }}	{{ row.flags }}	{{ row.text }}
No sentence flags at the current thresholds.

Word	Count	Syllables	Letters	First context	Copy
{{ row.word }}	{{ row.count }}	{{ row.syllables }}	{{ row.letters }}	{{ row.context }}
No long or complex word flags at the current thresholds.

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Readability scores estimate how heavy a passage may feel by looking at surface features such as sentence length, word length, syllables, and character counts. They are useful editing signals, not proof that a draft is accurate, complete, persuasive, or right for every reader.

Readability formula inputs flow into scores and revision flags

The same text can score differently across formulas because each formula values different clues. Some formulas weigh syllables, some weigh letters, and some respond sharply to long sentences or complex words. A spread between formulas is often a warning to inspect the passage instead of trusting one number.

Scores work best on ordinary English prose with enough words to measure. Very short samples, mixed-language text, headings, lists, and technical passages can produce unstable or misleading grade estimates.

Technical Details:

Readability formulas reduce a passage to measurable signals: words, sentences, letters, syllables, and complex words. The checker estimates syllables for English words, splits sentences according to the selected mode, and calculates both ease and grade-style results.

The consensus grade is the median of the grade-level formulas, while Flesch Reading Ease remains a separate score where higher values generally mean easier reading. Target profiles compare the consensus grade with a selected ceiling such as grade 6, grade 8, grade 10, grade 12, or grade 14.

Flesch Reading Ease = 206.835 - 1.015 \times words per sentence - 84.6 \times syllables per word

Readability formulas and signals used by the checker
Output	Inputs used	Reading cue
Flesch Reading Ease	Words per sentence and syllables per word.	Higher is easier; 60 to 70 is treated as standard plain prose.
Flesch-Kincaid Grade	Words per sentence and syllables per word.	Returns an estimated U.S. school-grade level.
Gunning Fog	Sentence length and complex-word share.	Rises when long sentences and 3+ syllable words increase.
SMOG Estimate	Complex words scaled to 30 sentences.	Marked as an approximation when the sample has fewer than 30 sentences.
Coleman-Liau	Letters and sentences per 100 words.	Uses character load instead of syllable load.
Automated Readability Index	Letters per word and words per sentence.	Emphasizes character count and sentence length.

Revision signals add judgment cues beyond formulas. Average sentence length above 22 words is marked heavy, flagged sentence share above 25 percent is high, complex-word share above 16 percent is high, formula spread above 4 grades is unstable, and samples under 100 words are marked short.

Everyday Use & Decision Guide:

Paste the real draft, not one polished paragraph. Choose Reader target for the audience first because the target badge and grade chart use that ceiling without changing the formula scores.

Use Standard punctuation with abbreviation guard for ordinary prose. Switch to Line-aware for sparse punctuation when reviewing bullet lists, slide copy, or notes where line breaks act like sentences. Use Punctuation only when line breaks should not create sentence boundaries.

Start with Readability Metrics to see consensus grade, reading ease, word count, and sentence count.
Open Formula Scores when formula spread is large and one grade number may be misleading.
Edit from Sentence Flags before replacing every technical term.
Use Word Load Flags to find repeated long or multi-syllable words worth explaining or simplifying.
Check Revision Signals for passive hints, adverb load, sample size, and target fit.

A lower grade does not guarantee better writing. If a necessary technical term is clear for the audience, keep it and shorten the sentence around it.

Step-by-Step Guide:

Run the check, then use the flagged rows as an editing queue.

Paste text into Source text, or load a plain text file. The summary should show a grade figure, reading ease, words, sentences, and the selected target profile.
Set Reader target. If the badge says Above target, use the revision rows before treating the draft as ready.
Choose Sentence splitting in Advanced. If a list is counted as one long sentence, switch to line-aware mode and compare the sentence count.
Adjust Long sentence threshold, Complex word threshold, or Long word threshold only when the default flags do not match the audience or house style.
Read Readability Metrics and Formula Scores, then open Sentence Flags and Word Load Flags for specific edit targets.
If Formula spread is mixed or unstable, use the flagged sentences and word rows rather than one formula score.

For a validation failure caused by empty input, paste text or load a file before reading the result tabs.

Interpreting Results:

Consensus grade is the best single grade estimate because it uses the median of the grade-level formulas. Flesch Reading Ease should be read separately: higher ease usually means faster scanning, while a lower grade usually means a lighter school-grade estimate.

Formula spread protects against false confidence. A spread above 4 grades means the formulas disagree enough that the sentence and word tables deserve more weight than the headline score.

A passage can fit Grade 8 target and still be unclear if it omits context, buries the main point, or uses terms the audience does not know. Verify the flagged rows against the actual reader and purpose.

Worked Examples:

A public notice with 420 words, 18 sentences, and a Consensus grade near grade 8 can fit the general public target. If Sentence Flags lists only two sentences above the 22-word threshold, editing those rows may be enough.

A technical release note with 180 words and many product terms may show Complex words and a high Gunning Fog score. Keep necessary product names, but use Word Load Flags to find repeated terms that need one plain definition.

A slide copied without punctuation may show one oversized sentence in standard mode. Switching Sentence splitting to line-aware mode should raise the sentence count and make Average sentence length reflect the actual bullets.

FAQ:

Can readability formulas judge writing quality?

No. The checker measures surface features and revision signals. It cannot verify accuracy, structure, tone, legal meaning, or whether the draft answers the reader's real question.

Why do technical words raise the score?

Many formulas count syllables, letters, or complex words. Long technical terms can raise Consensus grade even when the intended audience understands them.

Why did my bullet list count strangely?

The default sentence mode depends mainly on punctuation. For sparse bullets or slide text, choose Line-aware for sparse punctuation so line breaks can act as sentence boundaries.

Does it work for non-English text?

The formulas and syllable estimate are English-oriented. Revision Signals warns when non-ASCII letter share is high because mixed-language or non-English text can make the scores unreliable.

Glossary:

Consensus grade: The median of the grade-level readability formulas.
Reading ease: A Flesch score where higher values generally indicate easier reading.
Complex word: A word at or above the current syllable threshold, usually 3 or more syllables.
Formula spread: The gap between the highest and lowest grade-level formula results.
Reader target: The selected grade ceiling used for target-fit badges and chart reference lines.

References:

Measuring Readability, Indian Health Service.