AI Text Checker
Paste any text to see how AI-like it reads, with the sentences and phrases that triggered the score highlighted. Unlimited, no sign-up, and the text never leaves your browser.
This score is an estimate based on writing patterns. Each of the six signals below is scored from 0 to 100, then combined as a weighted average (stock phrases 26%, sentence-length variation 22%, repetition 20%, punctuation 14%, lists 10%, vocabulary 8%). It uses fixed rules, not a language model, so the same text always gets the same score.
Score by signal
What triggered it
Stock phraseTriadEm dashWavy underline = repetitive or phrase-heavy sentence
How to rewrite it
What the AI Text Checker looks at
Paste a piece of writing and you get a 0–100 score for how machine-like it reads, with the sentences and phrases that raised the score marked on your own text. There is no sign-up and no limit on how often you use it. Everything is calculated inside the browser tab you are looking at, so you can check a cover letter, an assignment or a work document without it leaving your device.
It works for English and Korean. The language is picked from the share of Hangul characters in the text, and each language has its own phrase list and thresholds.
The six signals
- Sentence-length variation People follow a long sentence with a very short one. Text from a language model tends to keep sentences at a similar length. The measure is the standard deviation of sentence length divided by the average.
- Repeated openers and endings In English, how many sentences start with a word that already opened another sentence. In Korean, how many sentences close on the same formal ending.
- Stock phrases Words that turn up far more often in AI writing: delve, moreover, furthermore, it's important to note, in conclusion, tapestry, a wide range of, and a few dozen more.
- Lists and triads The habit of grouping things in threes ("A, B, and C") and of numbered or bulleted lines, relative to the number of sentences.
- Vocabulary diversity The share of distinct words in each 50-word stretch. It drops when the same words keep coming back.
- Punctuation habits Frequent em dashes and colons raise the score; question marks, exclamation marks and ellipses lower it.
How to use it
- Paste your text into the box. It needs at least 200 characters and 3 sentences, because length variation and repetition cannot be measured on less.
- Press Check text. The score and a bar for each signal appear at once.
- Under "What triggered it", look at the highlighted phrases and the sentences with a wavy underline. Hover over an underlined sentence to see why it was flagged.
- Edit using the tips under "How to rewrite it", then check again to see how the score moves.
Reading the score
Below 35 means few machine-like patterns, 35 to 64 means some, and 65 or above means many. The number is counted from the surface of the text, so formal writing such as reports and academic papers can score high even when a person wrote it, and AI text edited into a conversational voice scores low. It is best used to find the stiff parts of your own writing and fix them, less so to decide who wrote something.
Rewriting tips that work
Start by deleting the highlighted stock phrases. Sentences usually survive without "moreover", "additionally" or "in conclusion". Next, where several sentences in a row open the same way, change the subject of one. Finally, swap vague wording such as "a wide range of options" for an actual number, a name or something you saw yourself. The text gets more readable whatever the score does.
When it helps
- Cover letters and applications After drafting with AI, check whether the result sounds like you. Replace paragraphs dense with stock phrases with sentences about what you actually did.
- Blog posts and newsletters One pass before publishing shows how many sentences open with "Moreover" and how often the same opener repeats.
- Essays and reports If your own writing gets called stiff, see which signal is high and fix only that part.
- Korean text Paste Korean and it is scored with Korean rules, including runs of the same sentence ending.
Good to know
Longer texts give steadier results. With barely 200 characters, changing one sentence moves the score a lot, so paste three or four paragraphs when you can. Leave out tables, code and headings and paste only the body text. The sample buttons let you compare how a human-written and an AI-written text differ on each signal.
FAQ
Is my text uploaded?
No. All the calculation happens in your browser and the text is not sent anywhere.
How is the score calculated?
Six signals are each scored 0–100 and combined as a weighted average: sentence-length variation, repeated openers and endings, stock phrases, lists, vocabulary diversity and punctuation. It is an estimate based on writing patterns.
How long does the text need to be?
At least 200 characters and 3 sentences. Longer texts give steadier results.
Does it work for Korean?
Yes. The language is detected from the share of Hangul characters and Korean text is scored with Korean rules.