AI Content Detector
Detect AI-generated content instantly using advanced AI detection models. Analyze ChatGPT, Claude, Gemini and other AI-generated text with fast and accurate results.
- Fast Detection
- Privacy Protected
- Accurate Results
- Free Daily Scans
Scan Your Text
Detection Results
- Human: —
- Mixed: —
- AI: —
Confidence
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Writing Style
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Sentence Complexity
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Readability
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Human Score
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AI Score
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Human vs. AI-Written
A look at how the detector reads two different samples.
Human-Written
I almost didn't make the trip. It rained the whole drive up, and honestly, I nearly turned back twice. But the moment the clouds broke over the ridge, I was glad I hadn't.
AI-Generated
The trip was a wonderful experience filled with beautiful scenery. Despite the rain, the journey proved to be rewarding and memorable in many ways.
Everything a Detector Should Do
Accurate AI Detection
Multi-model scoring reduces false positives compared to single-model checkers.
Supports ChatGPT
Trained to catch GPT-3.5 and GPT-4 style phrasing and structure.
Supports Claude
Recognizes the longer, hedged sentence patterns typical of Claude output.
Supports Gemini
Detects list-heavy, structured phrasing common in Gemini responses.
Fast Scanning
Get a full breakdown in seconds, no matter the length of your input.
Privacy First
Scanned text isn't stored unless you choose to save it to your history.
How It Works
Paste your content
Drop any text into the scanner above.
Click Scan
RewriteAI checks it against multiple detection models.
Review AI detection score
See the full breakdown, then humanize if needed.
Why Choose RewriteAI?
- Accurate Detection
- Fast Results
- Privacy Protected
- Easy to Use
- Multi Model Analysis
- Professional Reports
Frequently Asked Questions
What is an AI detector?
A tool that analyzes text and estimates the probability it was written by an AI model, based on signals like perplexity and burstiness.
How accurate is RewriteAI's AI detector?
It aggregates several detection models rather than relying on one, which reduces false positives. Submit at least 150–200 words for the most reliable score.
Can it detect ChatGPT text specifically?
Yes, along with Claude, Gemini, Llama, Mistral, and other large language models.
Is the AI detector free?
Yes, with 10 scans per day on the free plan and no credit card required.
How do I use the AI detector?
Paste your text, click Scan for AI, and review the Human, Mixed, and AI percentage breakdown.
How is this different from GPTZero or Turnitin?
RewriteAI combines multiple detection signals and connects directly to the humanizer, so flagged text can be rewritten in the same place.
Can it flag human-written text by mistake?
Yes, occasionally, especially with highly formal or repetitive writing. This is a known limitation across all AI detectors.
What AI models can it identify?
ChatGPT, Claude, Gemini, Llama, Mistral, Copilot, and other major AI writing tools.
How much text do I need for an accurate result?
At least 150–200 words. Snippets under 50 words often return inconsistent scores.
What if my content scores as AI-written?
Send it to the AI Humanizer in Aggressive mode, then re-scan the result.
The Complete Guide to AI Content Detection
What Is an AI Detector?
An AI detector is a tool built to answer one question: was this text likely written by a person, or generated by a language model like ChatGPT, Claude, or Gemini? Rather than reading for meaning, an AI checker looks at statistical patterns in how the words and sentences are put together. It's the same basic approach used by tools like GPTZero and Originality.ai, and RewriteAI's detector applies that same method, aggregated across multiple models, to give you a broader, more balanced read on any piece of text.
The Signals Behind AI Detection
Two measurements do most of the work in AI content detection. Perplexity measures how predictable each word is, given the words before it. Language models tend to choose the statistically likely next word more often than a human writer would, which makes AI text score lower on perplexity, more predictable, more uniform. Burstiness measures how much sentence length and structural complexity vary across a passage. Human writing naturally bursts: a short sentence, then a long one, then a fragment for emphasis. AI-generated text tends to even that out, producing a steadier, more uniform rhythm from one sentence to the next. A detection tool combines these signals, along with vocabulary diversity and phrase-level patterns, into a single probability score.
Why RewriteAI Uses a Multi-Model Approach
No single AI detector is perfect. Each model is trained on a slightly different set of examples and tuned to catch slightly different patterns, which means any one detector can produce false positives on unusual but genuinely human writing, or miss AI text that's been lightly edited. RewriteAI's detector checks a passage against several models at once and returns an aggregate result, so the score you see reflects a consensus rather than a single model's opinion. This tends to be more stable than relying on one classifier alone, though as with any AI detector, no score should be treated as absolute proof.
Detecting ChatGPT, Claude, and Gemini
Each major AI model has recognizable habits. ChatGPT output often leans on certain transition phrases and keeps a fairly even paragraph rhythm. Claude tends to produce longer, more hedged sentences with qualifying language. Gemini responses often lean list-heavy and structured. RewriteAI's detector isn't limited to catching just one of these; it's built to recognize the broader statistical fingerprint, low burstiness, predictable phrasing, uniform sentence rhythm, that shows up across most current language models, which is what makes it useful as a general-purpose AI checker rather than a single-model detector.
Reading Your Detection Results
A scan returns three numbers: Human, Mixed, and AI. These represent the model's confidence that the passage falls into each category, not a literal percentage of words written by each source. A high AI score means the statistical patterns in your text closely resemble typical language-model output. A high Mixed score usually means the passage has some AI-typical patterns alongside more natural variation, which is common in text that's been AI-drafted and then lightly edited by a person. The extended breakdown on this page adds a few more data points, confidence, writing style, sentence complexity, and readability, calculated directly from your text, to give a fuller picture beyond the single headline score.
Why AI Checkers Sometimes Get It Wrong
False positives happen across every AI content detector, including well-known tools like Turnitin and GPTZero. Writing that's highly formal, technical, or repetitive by nature, legal contracts, scientific abstracts, structured reports, can score higher on AI probability even when it's entirely human-written, simply because that style of writing naturally has lower burstiness. If you believe a genuinely human piece has been flagged incorrectly, running it through a light humanizing pass to add natural sentence variation is a reasonable way to reduce the score without changing what the text says.
Using an AI Checker Before You Publish or Submit
Scanning content before it goes out, whether that's a student paper, a client deliverable, or a blog post, gives you a chance to catch issues before someone else does. For students, checking a draft ahead of submission can flag passages that might draw scrutiny from an institution's own detection software. For content teams, scanning AI-assisted drafts before publishing helps confirm the final copy reads naturally, regardless of how the first draft was produced. In both cases, the goal is the same: know your score before someone else finds out for you.
From Detection to Humanizing
Detecting AI text is only half the workflow. If a scan comes back with a high AI score, the natural next step is rewriting, not just for the sake of a lower number, but because more natural sentence variation genuinely improves readability. RewriteAI's AI Humanizer is built to work directly with this detector: paste the flagged text into the humanizer, choose a rewrite mode, and re-scan the result here to confirm the score has dropped. Keeping detection and rewriting in the same toolset removes the friction of switching between separate apps.
Limitations Worth Knowing About
No AI detection tool, including this one, should be treated as definitive proof of how a piece of text was produced. Detection models work probabilistically, and both false positives and false negatives are a known part of how the technology currently performs, especially on very short passages, heavily edited AI drafts, or writing in a second language. Treat detector scores as a useful signal to guide editing decisions, not as a courtroom-grade verdict, and always check the policies of the specific institution or platform you're submitting to.
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