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How hard is this book to read?

Drop in any EPUB (or plain-text file) and instantly see its reading grade level, how rich its vocabulary is, and the small set of words that carry most of the book.

By Jeremy Lee

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total words

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unique words

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vocabulary richness (TTR)

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reading ease (0–100)

The 20 most frequent meaningful words (stopwords removed).

How much of the whole book the most common words cover.

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What the numbers mean

Reading grade level (Flesch–Kincaid) estimates the U.S. school grade needed to read the text comfortably. Reading ease runs 0–100, higher = easier. Vocabulary richness (TTR) is the ratio of unique words to total words: lower means more repetition. The coverage curve shows how few distinct words you actually need to follow most of the book — the same lens I used to study the language of reality TV in my Love Island lexical analysis.