How to Check If Text Is AI-Generated

As AI writing models have improved, the gap between AI-generated and human-written text has narrowed significantly. Text that once sounded obviously robotic — repetitive, generic, oddly formal — now passes casual reading without raising flags. For educators, publishers, and anyone who needs to verify the origin of text, detection tools have become essential.

AI detection tools work primarily by analyzing statistical properties of the text. They measure 'perplexity' — how predictable the text is relative to a language model's expectations — and 'burstiness' — how much sentence length and complexity varies. AI-generated text tends to be low-perplexity (predictable, consistent) and low-burstiness (uniform sentence variation). Human writing tends to have higher variation in both.

Certain stylistic patterns are also associated with AI text: overuse of transitional phrases like 'In conclusion' and 'It is important to note that', an absence of specific personal anecdotes or concrete examples, unnaturally even paragraph lengths, and a tendency to present 'both sides' without taking a clear position. No single signal is definitive, but multiple signals together raise the probability significantly.

paraphraserhumantext's AI detector provides a percentage confidence score along with a sentence-by-sentence breakdown showing which sections are most likely AI-generated. This per-sentence analysis helps identify mixed-origin documents — where some sections are human-written and others are AI-generated. Like all detection tools, it should be used as evidence rather than proof: human review of flagged content is always the appropriate final step.