How to Tell If Something Was Written by AI: 12 Signs and a Step-by-Step Check

1. Generic statements that could fit any article

AI models are trained to produce the most likely continuation of a prompt, so they often default to safe, universal claims: “Technology is rapidly transforming the way we live and work.” If you could paste a sentence into a dozen different articles without changing a word, it is a warning sign.

2. Missing first-hand experience and specific detail

Human writers naturally include names, places, numbers, dates, anecdotes and opinions formed from experience. AI text frequently lacks these or invents vague stand-ins (“a recent study,” “many experts”). Ask: does this piece contain anything only this writer could know?

3. Uniform rhythm and paragraph length

Detectors call this low burstiness. Paragraph after paragraph runs three to four sentences of similar length, each opening with a topic sentence and closing with a neat summary. Human writing tends to be messier — a one-line paragraph here, a long digression there.

4. Stock transitions and overused phrases

Certain phrases appear far more often in chatbot output than in typical human writing. Watch for:

• “Moreover,” “Furthermore,” “Additionally” at the start of many sentences
• “It's important to note that…” and “It's worth mentioning…”
• “In today's fast-paced world” or “In the ever-evolving landscape of…”
• “Delve into,” “navigate the complexities,” “a testament to,” “unlock the potential”
• “In conclusion,” followed by a restatement of the introduction

One or two of these mean little. A text dense with them is worth a closer look.

5. Balanced but non-committal opinions

Ask an AI for a view and it often presents “both sides,” lists pros and cons, and concludes that “the best choice depends on your needs.” When a piece that should argue a position never actually takes one, that hedging is a common AI pattern.

6. Confident factual errors and invented sources

LLMs can “hallucinate” — producing plausible facts, quotes, statistics or citations that do not exist. Spot-check any specific claim. A reference to a real-sounding journal article that you cannot find anywhere is one of the strongest signs of unedited AI text.

7. Perfect grammar with flat voice

Flawless spelling and punctuation are not suspicious by themselves. The tell is the combination of perfect mechanics with no personality: no humor, no strong word choices, no regional expressions, no rough edges.

8. Over-structured formatting

Chatbots love headings, bolded lead-ins and bullet lists with exactly three or five items. Short answers that arrive with headers and a summary section, or emails formatted like reports, often come from AI.

9. Repetition of the prompt's wording

AI answers frequently echo the question: “Here are some effective strategies for improving employee engagement.” In essays, the assignment prompt may be restated almost verbatim in the first and last paragraphs.

10. A sudden shift in style

If a student's or colleague's writing suddenly changes vocabulary, tone or quality — or if one section of a document reads very differently from the rest — part of it may have been generated or pasted from elsewhere.

11. Outdated or oddly generic references

Models have training cutoffs and may describe “the latest” tools or events that are already old, or avoid naming any specific product, person or date at all.

12. Leftover chatbot artifacts

Occasionally the evidence is obvious: “As an AI language model…”, “Certainly! Here's a…”, “I hope this helps!”, placeholder brackets like [Your Name], or markdown symbols such as ** and ### pasted into a document.

Step-by-step: how to check if text was written by AI

When you need a careful answer rather than a gut feeling, follow this process:

• Read the full text once without judging, noting any of the 12 signs above.
• Verify two or three specific facts, quotes or citations.
• Compare with known samples of the writer's previous work.
• Paste the text (ideally 300+ words) into a free AI detector and review the highlighted sentences, not just the score.
• If the result is borderline, test a second detector and note whether they agree.
• When the stakes are high, talk to the writer: ask about their sources, drafts and reasoning.

This combination of human reading and AI detection is far more reliable than either on its own.

What not to do

Do not accuse someone based on a single sign or a single detector score. Formal writers, non-native English speakers and people who rely on grammar tools are especially likely to trigger false alarms. Remember that using AI is not always against the rules — many workplaces and classrooms allow it for brainstorming or editing — so clarify expectations before drawing conclusions.

Final thoughts

Learning how to tell if something was written by AI comes down to pattern recognition: generic claims, missing specifics, uniform structure, stock phrasing and unverifiable facts. Use these signs to decide what deserves a closer look, back them up with an AI checker, and keep human judgment at the center of any decision.

Frequently asked questions