BareGPT
AI Detection With Evidence

How our AI detector
actually works

No black box. Here are the signals we analyze, how the score is built, and why every result comes with a confidence range instead of fake certainty.

Our Core Principle: Accountability

A detection score you can't interrogate is just an accusation. Every BareGPT result shows which sentences drove the score, which signals fired, and how confident the read is — so a flagged result is the start of a fair conversation, not a verdict.

Inside the Detector

What we analyze and how the result is built

Signals We Analyze

Twelve stylometric signals: sentence-length uniformity, n-gram repetition, transition density, vocabulary variety, function-word ratio, character entropy, punctuation patterns, sentence-opening repetition, compressibility, and structural formatting.

Evidence, Not Just a Score

Every scan shows the exact sentences that drove the score and the reason each was flagged — plus a per-signal breakdown of how much each pattern contributed to the final result.

Calibrated Thresholds

Verdict thresholds are calibrated against test sets of known human and AI writing, and results include a confidence interval that widens for short or ambiguous text — so you always know how much to trust a score.

Limitations — Stated Honestly

No AI detector is proof. Polished human writing can look model-like; edited AI text can look human. Every report states its false-positive risk, and we recommend detection be used to start a conversation, never to end one.

How It Works

From paste to evidence report in four steps

01

Paste or Upload Text

Drop in the text you want to check — 150+ words gives the most reliable read.

02

Get a Score With a Range

A 0–100 score, a verdict, a confidence interval, and an explicit false-positive risk.

03

Review the Evidence

See the exact sentences that drove the score and why each one was flagged.

04

Export the Report

Download a PDF evidence report you can share — or compare the draft against a known writing sample.

Beyond Detection: Proving Authorship

Detection analyzes a finished text — which means it can only ever estimate. Authorship verification works differently: write in BareGPT's editor and it records your drafting process as it happens — revisions, progress, and time spent. If your work is ever questioned, you have evidence of how it was written, which no detector score can provide or refute.

You can also compare a draft against a known writing sample with the style fingerprint: we measure sentence cadence, rhythm variation, transition habits, vocabulary variety, and punctuation patterns against the author's baseline and flag deviations with explanations.

Your Data is Protected

Content is transmitted securely over HTTPS/TLS encryption and stored with industry-standard security measures. We do not use your content to train AI models without explicit consent.

Privacy First

Text you scan remains your intellectual property. For complete details on data retention, access controls, and your rights, please review our privacy policy.

A detection score is evidence, not proof

No AI detector can prove how a text was written. Use scores and evidence to inform a fair conversation — never as the sole basis for an accusation, a grade, or a decision about someone's work.

Frequently Asked Questions

Common questions about how detection works

How does the AI detector work?

BareGPT analyzes stylometric signals in your text — sentence-length uniformity, phrase (n-gram) repetition, transition density, vocabulary variety, function-word ratios, character entropy, punctuation patterns, and structural formatting. Each signal is weighted and combined into a 0–100 score, and every scan shows you which signals contributed and by how much.

What do the scores mean?

Lower scores indicate the text reads like natural human writing; higher scores indicate model-like patterns. Thresholds are calibrated against test sets of known human and AI text. Scores in the middle mean mixed signals — which we tell you honestly instead of forcing a verdict.

Why do you show a confidence range?

Because a single number overstates certainty. Every result includes a confidence interval based on text length and signal strength, plus an explicit false-positive risk. Short or stylistically unusual text produces wider ranges — and we say so.

Can a detector score prove someone used AI?

No. No detector — ours included — can prove authorship from the final text alone. Scores are risk signals to support a fair conversation. That's why we pair detection with authorship verification, which records the writing process itself.

What is the style fingerprint?

You can provide a known writing sample from an author, and BareGPT compares the draft against it across sentence cadence, rhythm variation, transition usage, vocabulary variety, and punctuation habits. Deviations from the author's natural style are flagged with explanations.

What is authorship verification?

When you write in BareGPT's editor, it builds a record of your drafting process — revisions and progress over time. If your work is ever flagged by a detector, you can produce evidence of how it was written, not just a score arguing in your favor.

How much text do I need for a reliable scan?

At least 150 words; 400+ words gives noticeably steadier results. More text means more patterns to analyze, a narrower confidence range, and lower false-positive risk. Very short text produces low-confidence results, and we label them as such.

What text types work best?

BareGPT is designed for prose in English: essays, articles, reports, application letters, and professional writing. Poetry, code, heavily technical writing, and highly formatted documents produce less reliable signals.

See the evidence for yourself.

Scan any text free right now — no account, no credit card.