Novel Score
Calculates the Type Token Ratio (Expressive Vocabulary) in any text.
Novel Score will calculate an approximate TTR (Type Token Ratio) of any standard text. Simply copy and paste, then analyze. Novel Score will also get gather and rank said text's most commonly used words.
This tool was originally built to analyze the word variance of different authors. To a certain extent, TTR is a measure of one's expressive vocabulary, and thus writing ability.
However, take any results with a grain of salt.