Free AI Detector

How this AI detector works

Large language models write with habits. They repeat the same words, the same sentence shapes, and the same rhythm. This tool checks your text against a catalog of those habits. The catalog is based on Wikipedia's "Signs of AI writing" guide. Editors there built it by cleaning up thousands of AI-written articles. It's the same checklist experienced editors use to detect AI writing by eye.

The detector scores your text on two levels:

• Sentence patterns. Each sentence is checked for AI vocabulary ("delve", "tapestry", "testament to"), formulaic structures ("not just X, it's Y"), tacked-on "-ing" endings, vague attributions, and leftover chatbot phrases. Each match has a weight. Enough weight turns the sentence yellow, then red.
• Document statistics. Human writers mix short and long sentences. AI keeps them eerily uniform. We measure that variation, plus em dash frequency and contraction use.

Both levels combine into the 0–100 score at the top. Higher means more AI-like.

What the highlights mean

A red sentence stacks several strong AI patterns. A yellow sentence has one solid tell or a couple of weak ones. The underlined phrases are the exact words that triggered a match. One "crucial" on its own never flags a sentence. Real people write "crucial" too. It takes a cluster of patterns to separate AI output from human-written text.

Why we show our work

Most AI detection tools hand you a percentage and stop. You can't ask a black box why it flagged your essay. That makes false accusations hard to fight and real problems hard to fix.

This tool names every pattern it finds, with the matched phrase right next to it. If we flag your sentence, you can see the reason. You can rewrite the phrase and watch the score drop in real time. That makes it useful as an editor, not just a judge.

Common patterns in AI content

These show up constantly in ChatGPT, Claude, and Gemini output. Human writers use some of them too, just far less often.

Pattern	Example	Why it's a tell
AI vocabulary	"delve", "tapestry", "testament to", "ever-evolving"	These words spiked in frequency after 2023. "Delve" became the poster child.
"-ing" analysis tails	"…, highlighting the importance of collaboration"	AI tacks a participle phrase onto sentences to add fake depth.
Negative parallelism	"It's not just a tool, it's a mindset"	A favorite AI rhetorical move. Humans use it sparingly.
Copula avoidance	"serves as", "stands as", "acts as a"	AI dodges plain "is" and "has" for something grander.
Uniform sentences	Every sentence lands at 18–22 words	Human rhythm is bursty. AI rhythm is metronomic.
Em dash overuse	Multiple dashes per paragraph — like this — everywhere	ChatGPT leans on em dashes far more than most people do.
Chatbot leftovers	"I hope this helps!", "As an AI language model…"	Assistant chatter pasted along with the answer. The smoking gun.

How accurate is AI detection?

Honest answer: no AI detector is proof, including this one. OpenAI shut down its own AI text classifier in 2023 over low accuracy. Every AI detection tool produces some false positives. Formal human writing can trip pattern checks. Lightly edited AI text can slip past them.

What a detector can do is measure how much a text leans on known AI habits. That's exactly what this one reports, with receipts. Use it to detect AI-generated content in submissions, edit your own drafts, or check a suspicious guest post. Don't use any detector score alone to accuse a student or a writer.

Frequently Asked Questions

What is an AI detector?

An AI detector, also called an AI content detector, is a tool that estimates whether a text was written by an AI model such as ChatGPT, Claude, or Gemini. This one works by matching the text against documented AI writing patterns and measuring statistical habits like uniform sentence length. It reports a 0–100 likelihood score and highlights the sentences that triggered it.

What do the yellow and red highlights mean?

Red sentences stack several strong AI patterns and are flagged with high confidence. Yellow sentences carry fewer or weaker patterns and are flagged with medium confidence. The underlined phrases inside them are the exact words that matched a known AI pattern, and the report below the editor names each one.

How accurate are AI checkers?

No AI detector is reliable enough to serve as proof, and any tool claiming near-perfect accuracy is overselling. False positives happen: formal human-written text can look AI-like, and edited AI text can look human. This tool is transparent about its evidence: it shows every pattern it found so you can judge the case yourself instead of trusting a bare percentage.

Does it detect ChatGPT, Claude, and Gemini?

Yes. The patterns it checks — AI vocabulary, formulaic sentence structures, uniform rhythm, em dash overuse — are shared habits of all major large language models, because they emerge from similar training. It does not identify which model wrote a text, only how strongly the text shows machine-writing patterns.

How much text do I need?

At least 40 words for a score, and 100 or more for a reading you can trust. Statistical signals like sentence-length variation need at least six sentences to mean anything. You can paste up to 30,000 characters, roughly 5,000 words, with no signup.

Is my text stored anywhere?

No. The entire analysis runs in your browser using JavaScript. Nothing you paste is sent to our servers, stored, or logged, which also makes the tool safe for unpublished drafts and confidential documents.

Can I use this to make my writing sound less like AI?

Yes, and it works well for that. Paste your draft, rewrite the underlined phrases, vary your sentence lengths, and watch the score fall as you edit. The pattern report doubles as an editing checklist.

More free tools live on the SEO tools hub. Writing a business description instead? The Business Description Analyzer checks readability and keyword use the same way.