L. Frank Baum · 1900
With the 5,000 most common English words you are at the 95% line here — the level the research calls instructional. Most sentences land without help.
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 95 of them.
Ready to start with a 5,000-word vocabulary. 39,679 words in total; at 150 words a minute for a non-native reader, about 4 h 25 min to finish. Average sentence length 17.6 words. Reaching 95% coverage on this book (the floor for readability) takes roughly 5,000 word families.
The opening of The Wonderful Wizard of Oz, 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.
Dorothy lived in the midst of the great Kansas prairies, with Uncle Henry, who was a farmer, and Aunt Em, who was the farmer’s wife. Their house was small, for the lumber to build it had to be carried by wagon many miles. There were four walls, a floor and a roof, which made one room; and this room contained a rusty looking cookstove, a cupboard for the dishes, a table, three or four chairs, and the beds. Uncle Henry and Aunt Em had a big bed in one corner, and Dorothy a little bed in another corner. There was no garret at all, and no cellar—except a small hole dug in the ground, called a cyclone cellar, where the family could go in case one of those great whirlwinds arose, mighty enough to crush any building in its path. It was reached by a trap door in the middle of the floor, from which a ladder led down into the small, dark hole.
👆 Tap any word to try it
Readii cuts this book into three-minute passages. Tap a word you don't know and its meaning in that exact sentence appears in place — no jumping out, no losing the thread.
The opening chapters are free — no account, no card.
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.