Free AI Content Detector

Test your text against Turnitin, GPTZero, Originality.ai, and more. Multi-detector analysis with sentence-level detail.

5 major detectors
Sentence-level detail
Instant & private
0 words
0%AI Score

Ready to scan

Checked with

TurnitinTurnitin
CopyleaksCopyleaks
Originality.aiOriginality.ai
GPTZeroGPTZero
Winston AIWinston AI
ZeroGPTZeroGPT
AI-generated
0%
AI-assisted
0%
Human-written
0%

How Our Free AI Detector Works

HumanizeThisAI's AI detector analyzes text across multiple dimensions to determine whether content was written by a human or generated by AI tools like ChatGPT, Claude, or Gemini. The detector examines sentence structure patterns, vocabulary distribution, perplexity scores, burstiness metrics, and stylistic markers that distinguish human from AI writing. Everything runs in your browser — your text is never sent to a server.

What the AI Detector Checks

  • Sentence burstiness — Human writing varies sentence length dramatically; AI writing is uniform. Learn about perplexity & burstiness
  • Vocabulary diversity — AI overuses certain words like "delve," "leverage," and "utilize"
  • Perplexity patterns — AI text is more predictable than human writing
  • Transition word density — AI uses transitions like "furthermore" and "moreover" excessively
  • Contraction usage — Human writing uses contractions naturally; AI writing avoids them
  • Compression patterns — AI text has more repetitive structural patterns than human writing
  • Sentence starter variety — AI reuses the same opening words; humans diversify naturally

AI Detectors We Compare Against

Our detector provides analysis comparable to GPTZero, Turnitin, Originality.ai, Copyleaks, and ZeroGPT — completely free and with no signup required. We simulate how each major detector scores your text so you can see where you stand before submitting. Read how AI detectors work

What to Do If Your Text Is Flagged

If our detector flags your text as AI-generated, use HumanizeThisAI's humanizer to semantically reconstruct it into natural, human-sounding writing. Unlike simple paraphrasers, our humanizer rebuilds text at the meaning level — achieving a 99.9% bypass rate across all major detectors. Start with 1,000 free words per month, no credit card required.

Last updated: March 2026

FAQ

Questions & answers

Everything you need to know about our AI detection tool.

How does the AI detector work?+
Our AI detector analyzes text patterns including sentence structure uniformity, vocabulary choices, punctuation patterns, and writing style variations. AI-generated text typically shows low 'burstiness' (uniform sentence lengths), overuse of certain words, and predictable patterns that our algorithm can identify.
Is this AI checker free to use?+
Yes! Our AI checker is completely free. Just sign in with Google to get instant results. It's the best free AI detector available online.
Which AI writing tools can it detect?+
Our AI text detector can identify content from ChatGPT, GPT-4, Claude, Gemini, Llama, and other major AI writing tools. We continuously update our detection algorithms to stay current with new AI models and LLMs.
How accurate is the AI text checker?+
Our AI text checker achieves approximately 85-95% accuracy on most AI-generated content. However, no detector is 100% accurate, and results should be used as guidance rather than definitive proof. Heavily edited AI content may score differently.
What should I do if my text is detected as AI?+
If your text shows high AI probability, you can use our AI Humanizer tool to transform it into natural human-like writing that bypasses AI detectors like GPTZero, Turnitin, and Originality.ai. The humanizer restructures your content while preserving the original meaning.
Can this detect paraphrased AI content?+
Simple paraphrasing often doesn't fully remove AI signatures. Our AI writing detector analyzes deeper patterns beyond just word choice. For content that needs to pass detection, our AI Humanizer performs semantic reconstruction rather than simple paraphrasing.
How does this compare to GPTZero or Turnitin?+
Unlike GPTZero or Turnitin AI detection which often require paid subscriptions, our AI detector is completely free. We offer instant results with detailed breakdowns, and uniquely include access to our AI humanizer to fix any detected AI content.
Can I check if text is AI generated from ChatGPT?+
Yes! Our ChatGPT detector specifically identifies content generated by ChatGPT and GPT-4. Simply paste your text and our GPT detector will analyze it for AI patterns characteristic of OpenAI's models, giving you a clear probability score.
Is this AI generated? How can I tell?+
To check if content is AI generated, paste it into our detector. We'll analyze sentence uniformity, AI vocabulary markers, transition word overuse, and other signals. You'll receive a percentage score indicating the likelihood the text was written by AI versus a human.
Does the detector work for academic essays?+
Yes, our AI detector works excellently for academic content. Whether you're checking essays, research papers, or assignments, our tool can detect AI text that might be flagged by academic AI detection tools like Turnitin. Students and educators both use our free tool to verify content authenticity.

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