Daniel Defoe · 1719
Reads steadily at a 5,000-word vocabulary. An unknown word here and there, usually carried by the sentence around it.
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 254 of them.
Finishable at 5,000 words, with the odd lookup. 121,196 words in total; at 150 words a minute for a non-native reader, about 13 h 28 min to finish. Average sentence length 50 words — on the long side, so the load comes from sentence structure as much as from vocabulary. Reaching 95% coverage on this book (the floor for readability) takes roughly 7,000 word families.
The opening of Robinson Crusoe, 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.
I was born in the year 1632, in the city of York, of a good family, though not of that country, my father being a foreigner of Bremen, who settled first at Hull. He got a good estate by merchandise, and leaving off his trade, lived afterwards at York, from whence he had married my mother, whose relations were named Robinson, a very good family in that country, and from whom I was called Robinson Kreutznaer; but, by the usual corruption of words in England, we are now called—nay, we call ourselves and write our name—Crusoe; and so my companions always called me.
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These are already built, and closest in difficulty to Robinson Crusoe.
Ordered by unknown words per 100. Lower reads easier; to step up a level, pick a higher number.
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.