How to learn Japanese by reading

Why does reading work so well for Japanese?

You learn a word a little more each time you understand a sentence that contains it. That is the idea behind comprehensible input and extensive reading, and it matters doubly in Japanese, because the hardest part of the language is on the page. Kanji can't be picked up from conversation or audio: you have to see them, again and again, in words you already half know.

Paul Nation, the vocabulary researcher, warns that what you gain from one reading is small and "very fragile": a word you don't meet again soon is lost. His answer is a lot of reading at the right level plus some direct study of the words. For Japanese that means stories you can mostly follow and a flashcard deck built from them.

Spacing helps too. Ordinary Japanese has no spaces, so a beginner can't always tell where a word ends. Contos stories put a space between words, which makes every word visible and tappable; the Japanese hub shows how the text grows from A1 to B1.

What should you read at each stage?

Difficulty is the choice that matters most. A text with too many unknown words turns reading into decoding. For Japanese, count characters rather than words, because word counts depend on where the spaces go.

Kanji density rises slowly, from about a quarter of the characters at A1 to about a third at B2. Chapters grow faster: an average B2 chapter is more than twice as long as an A1 one. Stamina is part of each step. If you aren't sure where you are, how to choose your level has a ten-minute test.

How do you read a Japanese chapter?

1. Read straight through for the story. Don't stop for every unknown kanji. Ask who, where and what happened.
2. Read again slowly. Now watch the particles and the end of each verb, where Japanese keeps its tense and politeness.
3. Tap only what blocks the meaning. If you can follow the sentence, keep going. For the reading of a new kanji word, check a dictionary when you save it.
4. Save phrases, not lone kanji. A whole phrase tells you how the word is used.

Here is a phrase worth saving whole, from the first chapter of the flagship series:

Saved as 顔を上げる (kao o ageru, to look up), it is one card that teaches a noun, a particle and a verb at once. Phrases like this recur across the library. The pounding heart at every cliffhanger is one: ドキドキ (dokidoki, the thump of a racing heart) appears in 11 of the 48 free A1 and A2 chapters, most often as 胸がドキドキする (mune ga dokidoki suru).

Why should you stay with one Japanese series?

A series brings back the same people, places and props, so their words and kanji come round without you planning it. We measured this across the free chapters of the Contos Japanese library. In the 12 A1 series, about 55% of the kanji in chapter 2 had already appeared in chapter 1 of the same series, against about 30% for chapter 1 of a different A1 series. At A2 the figures were 61% and 36%.

Part of that gap is names, which are written in kanji and recur within a series. But the same pattern holds for words: 61% of the words in an A1 chapter 2 already appeared in its chapter 1, against 43% across series. Reading one series through is a form of narrow reading, and it is why later chapters feel easier.

Then climb with a story you know. The Secrets of Sakura House is written separately at A1, A2, B1 and B2, so you can reread the same plot with harder Japanese each time; Japanese CEFR levels puts one line from each level side by side.