What it measures

Type-Token Ratio (TTR) measures your vocabulary richness — the ratio of unique words to total words. Higher diversity signals original, naturally-written content rather than keyword-stuffed or template-generated text.

Why it matters for AI

AI systems use lexical diversity as a quality signal to distinguish human-quality content from thin, repetitive pages. Content that uses varied vocabulary is perceived as more natural and authoritative. Very low TTR often indicates keyword stuffing or auto-generated content, which AI deprioritises.

TTR	Score	What it signals
< 25%	Low	Repetitive — may signal low-quality or auto-generated content
25–40%	Average	Standard for long-form content
≥ 40%	Good	Rich vocabulary — natural, original writing

How to improve

1. Use synonyms — Avoid repeating the same terms; vary your word choices
2. Write naturally — Focus on communicating ideas rather than optimising for keyword density
3. Vary sentence structure — Mix short punchy sentences with longer explanatory ones