Arthur Conan Doyle · 1892
About one unknown word every twelve at a 5,000-word vocabulary. Readable, but it wants support — and that band is also where readers most easily fall into flow.
Coverage = the share of words in the text you already know. The research gives two lines: 98% before independent fluent reading is realistic, 95% for the instructional level that needs support (Hu & Nation, 2000). Proper nouns are not counted as unknown — recognising that it is a name is enough; this book has 553 of them.
Comfortable from about 8,000 words, or read it with glosses. 104,562 words in total; at 150 words a minute for a non-native reader, about 11 h 37 min to finish. Average sentence length 14.4 words. Reaching 95% coverage on this book (the floor for readability) takes roughly 8,500 word families.
The opening of The Adventures of Sherlock Holmes, word for word. Tap any word you don't know and its meaning here appears beside it — no sign-up, tap as often as you like.
To Sherlock Holmes she is always _the_ woman. I have seldom heard him mention her under any other name. In his eyes she eclipses and predominates the whole of her sex. It was not that he felt any emotion akin to love for Irene Adler. All emotions, and that one particularly, were abhorrent to his cold, precise but admirably balanced mind. He was, I take it, the most perfect reasoning and observing machine that the world has seen, but as a lover he would have placed himself in a false position. He never spoke of the softer passions, save with a gibe and a sneer. They were admirable things for the observer—excellent for drawing the veil from men’s motives and actions. But for the trained reasoner to admit such intrusions into his own delicate and finely adjusted temperament was to introduce a distracting factor which might throw a doubt upon all his mental results. Grit in a sensitive instrument, or a crack in one of his own high-power lenses, would not be more disturbing than a strong emotion in a nature such as his. And yet there was but one woman to him, and that woman was the late Irene Adler, of dubious and questionable memory.
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Computed by Readii from the public-domain text (updated 2026-10-21), not estimated by hand. The Readii reading level is our own scale, anchored on unknown-word density; it is not the same system as Lexile or AR and does not convert directly. Unknown words are counted against a frequency list built from a large subtitle corpus, so the bands mean the same thing for any learner of English, whatever your first language. This is difficulty for a non-native reader, not a native-child reading level.