AI Content Detector

1. Paste your text. Up to 10,000 characters. Minimum 20 characters. Shorter snippets can't be reliably classified.
2. Click Analyze now. Six detectors start working in parallel. Each card shows its own progress: connecting, submitting, analyzing patterns, processing.
3. Read the stamp. When all engines finish, a HUMAN / MIXED / AI stamp appears with the consensus percentage.
4. Inspect sentence by sentence. Below the stamp, each sentence is underlined in colour. Hover any sentence to see its exact AI score and label.
5. Compare individual engines. Six cards below the text show each detector's score side by side. Useful when one engine disagrees with the others.

The text is checked by six separate detectors at once and their scores are combined. The six:

• QuillBot AI Detector. Returns chunk-level AI scores. Good at catching paraphrased and lightly edited AI text.
• ZeroGPT. One of the most widely used free detectors. Strong on long-form ChatGPT output.
• Originality.ai. Widely used by publishers and SEO agencies. Returns block-level fake probability and is tuned for the latest models.
• Copyleaks. Used by universities and enterprises. Trained on a wide corpus across multiple LLMs.
• Winston AI. Sentence-level scoring with high recall on academic and journalistic writing.
• Ahrefs. A fast, free AI checker from the SEO toolset, useful as an extra signal on web and marketing copy.

Each engine has different strengths and blind spots. The consensus average is far more reliable than any single score.

The overall percentage tells you how much of the text reads as AI, but not which parts. The per-sentence view does that.

After analysis, every sentence is underlined: green for likely human (≤30% AI score), yellow for mixed (31–60%), and red for likely AI-generated (above 60%). Hover any sentence to see the exact percentage and verdict in a tooltip.

The per-sentence scores come from averaging chunk-, block-, and sentence-level data returned by QuillBot, Originality.ai, and Winston AI. The highlights use the same engines as the overall verdict, not a separate model.

Handy for editors and teachers who only need to rewrite the AI-sounding paragraphs in an otherwise human article.

The detector got a major rewrite in 2026. What's new:

• Six engines instead of one. Previous versions ran a single in-house model. Now you get QuillBot, ZeroGPT, Originality.ai, Copyleaks, Winston AI, and Ahrefs in parallel.
• Consensus stamp. A clear HUMAN / MIXED / AI verdict based on the average of all six engines, with one obvious percentage.
• Sentence-level highlighting. Inline green/yellow/red underlines with hover tooltips.
• Detection of newer models. GPT-4o, o1, Claude 3.7, Gemini 2.5, Llama 3, Mistral Large, DeepSeek V3.
• Live progress per engine. Each detector card shows its own step (connecting → analyzing → processing) so you can see which one is still running.
• 10,000-character limit. Up from the previous 2,500.
• Skipped-engine handling. If your text is too short for one provider, the others still run instead of the whole check failing.

Each of the six engines returns an AI-probability percentage between 0 and 100. We average them and apply these thresholds:

• 0–15%, HUMAN. Green stamp. The text reads as human-written across every engine. Safe to publish or submit.
• 16–40%, MIXED. Yellow stamp. Some sections look AI-influenced. Worth a closer look at the red-underlined sentences.
• 41–100%, AI GENERATED. Red stamp. The majority of detectors flagged this as machine-written.

The per-sentence underlines use slightly different cutoffs (30 / 60) because individual sentences are noisier than a whole document, and you don't want one borderline sentence dragging the verdict.

If a single engine disagrees sharply with the others, its card will still show its own score so you can see the outlier.

• Teachers and professors. Quickly check student essays for ChatGPT and Claude. Sentence highlights show which paragraphs were generated, not just whether something was.
• Editors and publishers. Vet submissions from freelance writers and verify outsourced articles before they go live.
• SEO and content agencies. Audit content from writers, spot AI text that needs a human pass before Google sees it.
• Recruiters and HR. Detect AI-written cover letters, applications, and take-home assignments.
• Students. Check your own writing before submitting. Paraphrased AI text often still flags red, so this is the easiest way to catch it.
• Journalists. Verify quotes, statements, and source material that might have been machine-generated.
• Researchers. Audit datasets and citations for AI contamination.