Mark Twain · 1876
Roughly one unknown word in ten. Looking each one up will stall you; this one wants glosses that appear in place.
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 390 of them.
Advanced — read it with glosses. 71,652 words in total; at 150 words a minute for a non-native reader, about 7 h 58 min to finish. Average sentence length 14.4 words. Reaching 95% coverage on this book (the floor for readability) takes roughly 12,500 word families.
The opening of The Adventures of Tom Sawyer, 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.
“Tom!”
No answer.
“TOM!”
No answer.
“What’s gone with that boy, I wonder? You TOM!”
No answer.
The old lady pulled her spectacles down and looked over them about the room; then she put them up and looked out under them. She seldom or never looked _through_ them for so small a thing as a boy; they were her state pair, the pride of her heart, and were built for “style,” not service—she could have seen through a pair of stove-lids just as well. She looked perplexed for a moment, and then said, not fiercely, but still loud enough for the furniture to hear:
“Well, I lay if I get hold of you I’ll—”
She did not finish, for by this time she was bending down and punching under the bed with the broom, and so she needed breath to punctuate the punches with. She resurrected nothing but the cat.
“I never did see the beat of that boy!”
She went to the open door and stood in it and looked out among the tomato vines and “jimpson” weeds that constituted the garden. No Tom. So she lifted up her voice at an angle calculated for distance and shouted:
“Y-o-u-u TOM!”
There was a slight noise behind her and she turned just in time to seize a small boy by the slack of his roundabout and arrest his flight.
“There! I might ’a’ thought of that closet. What you been doing in there?”
“Nothing.”
“Nothing! Look at your hands. And look at your mouth. What _is_ that truck?”
“I don’t know, aunt.”
“Well, I know. It’s jam—that’s what it is. Forty times I’ve said if you didn’t let that jam alone I’d skin you. Hand me that switch.”
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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.