14 Signs Text Was Written by AI (With Examples)

By the Free AI Content Detector Team · Published October 14, 2026 · 9 min read

These are the same 14 signals our free detector checks — learn to spot them with your own eyes. Remember: one sign means little. Five together is a pattern.

1. Cliché AI phrases. Models overuse a fixed set of phrases. Watch for "delve," "in today's fast-paced world," "it's worth noting," "navigate the complexities," "a testament to."
   "In today's fast-paced world, it's worth noting that businesses must delve into digital strategies."
2. Uniform sentence length. Count words per sentence — if nearly every sentence is 15–22 words, that's metronomic AI rhythm. Humans vary: short punches, long unwinds.
3. Zero contractions. AI writes "do not," "cannot," "it is." Humans write "don't," "can't," "it's" — even in formal contexts, occasionally.
4. Flat punctuation. Commas and periods only. No em dashes, no semicolons used playfully, no rhetorical questions. Human writing has texture.
5. Repetitive openers. "The study shows… The results indicate… The data suggests…" — paragraph after paragraph starting identically.
6. Transition-word stuffing. "Furthermore," "moreover," "additionally," "consequently" — used far beyond human frequency to glue ideas together.
7. No first person. AI defaults to impersonal voice. "I noticed," "we found," "my experience" are rare in raw model output.
8. Hedging everywhere. "It is important to note," "it should be mentioned," "generally speaking" — qualifiers that pad without adding meaning.
9. Listicle formatting. Everything becomes bullet points — even topics that deserve flowing prose. Models love structure; humans tolerate mess.
10. Formulaic conclusions. "In conclusion," "overall," "in summary" followed by a neat restatement. Human endings are messier and more varied.
11. Adverb inflation. "Significantly," "effectively," "truly," "deeply" — "-ly" adverbs doing the work that concrete detail should do.
12. No burstiness. Related to #2 but distinct: humans cluster — a flurry of short sentences, then a long one. AI spreads evenly throughout.
13. Generic examples. "For example, a company might…" — hypothetical, unnamed, detail-free. Humans cite specifics: names, numbers, places.
14. Emotional flatness. No humor, no irritation, no genuine surprise. Competent, balanced, and utterly devoid of a pulse.

The caveat that matters

Formal human writing — legal memos, technical docs, non-native English — can show several of these signs innocently. That's why manual reading complements tools but never replaces evidence. Run suspicious text through our free detector for the full 14-signal analysis, then interpret the score correctly.

Last updated: October 14, 2026.