AI Text Checker

Scans your writing for patterns commonly seen in AI-generated text — and shows you exactly what it found, so you can learn from it.

By Alex van den Berg · Last reviewed 30 July 2026 · How we test our tools

Read this before you use it: this is a heuristic pattern-checker, not a certified AI detector. It cannot prove text is or isn't AI-written, and it can be wrong in both directions — formal, careful, or non-native-English writing often triggers false positives on every AI detector, including this one. Use it to understand your own writing style, not as proof for or against an accusation.

Paste your text

Add a bit more text — at least 40-50 words — for a meaningful check. Very short passages don't give these signals enough to work with.

How this — and real AI detectors — actually work

Real AI-detection tools like GPTZero and Turnitin's detector use two main ideas: perplexity (how "surprised" a language model is by the next word — AI text tends to be predictable) and burstiness (how much sentence length and complexity vary — human writing tends to be uneven, AI text more consistent). Those tools train a classifier on this and other signals from huge datasets.

This checker doesn't have a trained model — it's a transparent set of rules you can read for yourself: a list of stock phrases that show up disproportionately often in AI writing ("delve into", "in today's fast-paced world", "plays a crucial role"), a rough measure of sentence-length evenness as a stand-in for burstiness, and a few smaller signals like contraction use and repeated transition words. It's less accurate than a trained model, but it's honest about that, and it shows you every reason behind the score instead of hiding it behind a black-box percentage.

Independent research — including a widely cited Stanford study — has found that commercial AI detectors misclassify non-native English speakers' writing as AI-generated at a much higher rate than native speakers', because more formal, less idiomatic phrasing scores similarly to AI output on these exact signals. That's a real limitation of the whole category of tool, not just this one.

Phrases that make writing sound machine-generated

These show up disproportionately often in AI-generated text. None of them are "wrong" to use — but if your writing leans on several of these, it can read as generic even when every word is your own.

If your work gets flagged as AI-written

Keep your process. Google Docs and Word both save version history automatically — it's one of the clearest ways to show a document was written and revised over time, not generated in one shot.
Keep your drafts and notes. Outlines, research notes, and earlier drafts are evidence a detector can't produce.
Ask what specifically was flagged. A score alone isn't an explanation — ask to see which sections and why.
Stay calm and factual. False positives are a known, documented limitation of every AI detector on the market, not just an excuse — you're allowed to push back on a flag with evidence.
Know your institution's actual policy. Most schools require more than a single automated score as grounds for an academic integrity case.

Frequently Asked Questions

Is this an accurate AI detector?

No — and you should be skeptical of any tool that claims to be. This checker looks for a handful of writing patterns often associated with AI text (stock phrases, unusually uniform sentence lengths, few contractions) and shows you exactly what it found. Even commercial detectors like Turnitin's or GPTZero, which use trained models, have documented false-positive and false-negative rates. Treat this as a style self-check, not proof of anything.

Why did my own writing get flagged?

Formal academic writing naturally shares traits with AI text: it avoids contractions, uses transition words like "furthermore" and "moreover", and often has consistent sentence structure. Non-native English speakers and careful, methodical writers are especially likely to trigger false positives on any AI detector, including this one — this is a well-documented, real problem, not a rare edge case.

What should I do if a teacher's AI-detection tool flags my work?

Keep evidence of your writing process: drafts, outlines, and version history (Google Docs and Word both keep an editable history you can show). Explain your process calmly and ask what specifically was flagged. Most institutions' policies require more than a single automated score as evidence — a heuristic or ML flag is a prompt for a conversation, not a verdict.

Is my text uploaded anywhere?

No. Every check runs as plain JavaScript in your browser. Nothing is sent to a server, logged, or stored — you can verify this by disconnecting from the internet after the page loads and running a check.

Can I use this to make sure my AI-assisted writing won't get caught?

That's not what this tool is for, and no tool can reliably guarantee that. It's built to help you understand what makes writing sound generic or machine-like, so you can add your own voice, vary your sentence structure, and write more naturally. Using AI to write work you submit as entirely your own is an academic integrity issue at most institutions regardless of whether a detector catches it — check your school's specific policy.