Blog · October 7, 2026

How Accurate Are AI Detectors? What the Evidence Shows

AI detectors feel authoritative — a confident percentage, a clear verdict. But how accurate are they really? The honest answer: useful as a signal, unreliable as proof.

How detectors decide

They don't detect AI directly. They measure statistical traits — how predictable the wording is (perplexity) and how much sentence length varies (burstiness) — and estimate a probability. Because these are correlations, they can be fooled in both directions.

False positives are the real problem

Detectors regularly flag genuine human writing as AI. Plain, even styles trip them up, and studies have shown they disproportionately misclassify writing from non-native English speakers. There have been real cases of students wrongly accused based on a detector score.

False negatives too

Lightly edited AI text often passes as human. So a "human" verdict doesn't prove a human wrote it either.

How to read a score responsibly

• Treat it as one weak signal, never as evidence of authorship.
• Never make a high-stakes decision — a grade, a firing — on a detector alone.
• Use it to spot generic, low-effort passages and improve them.

That's how we built our AI detector: to help you find and fix weak writing, with a clear note that the result is an estimate.