Free Burstiness Checker
See the rhythm of your writing. The checker turns every sentence into a bar, measures how much your sentence lengths vary, and scores the variety against what edited prose typically shows. Flat, same-length sentences are the fastest way for a draft to read machine-made and monotonous; this page makes the pattern visible so you can fix it where it matters.
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How to check sentence variety in three steps
Paste your text
A paragraph is enough to start; a section or chapter gives the most meaningful picture. There is no word limit.
Read the rhythm
The rhythm line plots one point per sentence: the straighter the line, the flatter and more AI-like the structure; the more jagged, the closer to human writing. Bars below give the exact words per sentence.
Revise for contrast
Cut the key claim in each paragraph short, merge thin sentences, split overloaded ones. Watch the variation score move as you edit.
Why this burstiness checker is different
The rhythm made visible
The same sentence-length rhythm line our humanizer dashboard uses, drawn large: flat stretches and spikes are visible at a glance, which is more actionable than a single score.
Length-independent measure
Variation is measured relative to your average sentence length, so a dense theoretical text and a plain-English summary are judged by the same standard.
Benchmarks for research prose
Bands calibrated for academic writing, with allowance for legitimately uniform stretches such as procedural methods text.
Statistics, not verdicts
The tool reports sentence-length data and nothing else. No authorship claims, no detection promises: numbers you can check by hand.
Sentence rhythm: the statistic behind readable prose
Read a page of good academic prose aloud and you will hear it: long explanatory sentences that build a case, punctuated by short ones that close it. The alternation is not decoration. Sentence length is one of the few tools written English has for emphasis, and writers spend it deliberately: the forty-word sentence does the work, the six-word sentence makes the point stick. Stylometrists call the resulting statistical signature burstiness, and it is one of the most stable differences between drafted and edited prose.
Flat rhythm has always existed; committee reports were monotone long before language models. But AI drafting has made it common enough that readers now notice. A model generating the most probable continuation gravitates toward average sentence shapes, so raw chatbot output often runs sentence after sentence within a few words of the same length. Professors and reviewers who read hundreds of pages a week pick up the pattern quickly, not as proof of anything, but as a signal that a draft has not been revised by a human ear. A text that varies is a text someone listened to.
The fix is an editing pass with the chart open. Find the claim sentence in each paragraph and strip it to its core. Merge consecutive thin sentences that share a subject. Split any sentence that chains three clauses with commas and conjunctions. Read the paragraph aloud and let your breath find the joints. The variation percentage will rise on its own, and unlike chasing a score, every one of those edits also makes the prose better, which is the point.
Rhythm is one layer of natural-sounding text. For vocabulary-level signals, see the AI word cleaner, and for the full craft, our guide on making AI writing sound human.
How to read the rhythm line
One point per sentence, plotted by length. The shape tells you more than the score does.
Every sentence lands within a couple of words of the last. This is the flat, machine-like structure typical of unedited AI drafts: grammatically clean, rhythmically monotone. Readers feel it before they can name it.
Long explanatory sentences alternate with short, pointed ones. This is the natural rhythm of human writing that has been read aloud and revised: the long bars build the case, the short ones land it.
Aim for jagged, not random. Each spike should be a choice: a short sentence placed where the claim needs weight, a long one where the argument needs room. The dashed average line in the chart shows what your sentences deviate from; prose that never leaves it is prose nobody has listened to.
Who uses the burstiness checker
Researchers and PhD students
Check whether AI-assisted or quickly drafted sections read flat before a supervisor or reviewer notices the monotone.
Students
See why an essay feels repetitive and learn the short-after-long technique that makes arguments land.
Writers and editors
Diagnose rhythm at a glance when a piece reads dull and the usual line edits are not finding the cause.
ESL and non-native writers
Sentence-length monotony is a common habit when writing in a second language. The chart shows it instantly and progress is measurable.
Burstiness checker FAQs
What is burstiness in writing?
Does this tool detect AI writing?
What is a good variation percentage?
Is my text uploaded to a server?
Rhythm is one layer. Rewrite all of them.
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