onyomi-vs-kunyomi

Every learner of Japanese eventually hits the same wall: you look up a kanji and find two completely different readings listed — one labeled on’yomi, another labeled kun’yomi. Which one do you use? Why does 山 sometimes sound like san and other times like yama? This guide breaks down the two reading systems clearly, gives you the patterns that native learners use without thinking, and helps you build the intuition to choose correctly — even without a dictionary.

At a Glance: On’yomi vs Kun’yomi

What Is On’yomi? (音読み — The Chinese-Origin Reading)

On’yomi literally means “sound reading.” These readings were borrowed from Chinese pronunciation when kanji were imported into Japan, beginning roughly in the 5th century CE. Because Chinese was borrowed at different historical periods and from different regional dialects, some kanji actually have multiple on’yomi (more on that later).

The key thing to remember: on’yomi readings are the “Chinese-flavored” sounds. They are typically short — one or two syllables — and they are almost always used when a kanji appears alongside other kanji in a compound word (called a jukugo, 熔語).

Here are clear examples of on’yomi in compound words:

Notice that in every case above, you are reading two or more kanji together as a single word. That is the strongest signal for on’yomi.

Yuka

So on’yomi is like the “academic” or “formal” reading? It feels more technical to me.

Rei

That is a great way to think about it! On’yomi often appears in academic vocabulary, technical terms, and formal writing — because those words were coined using Chinese-borrowed building blocks. It is similar to how English uses Latin and Greek roots for scientific or formal words.

What Is Kun’yomi? (訓読み — The Native Japanese Reading)

Kun’yomi means “meaning reading.” These are the native Japanese words that existed before kanji arrived. When Chinese characters were imported, the Japanese matched each character to an existing Japanese word that shared a similar meaning. That native Japanese pronunciation became the kun’yomi.

Kun’yomi readings are typically longer than on’yomi — often two to four syllables — and they frequently appear with hiragana attached (called okurigana). That trailing hiragana is a strong visual signal that you are looking at a kun’yomi word.

In everyday conversation, kun’yomi readings are extremely common because they cover the basic vocabulary of daily life: eating, drinking, sleeping, colors, sizes, family members, body parts, and simple actions. These words existed in Japanese long before Chinese influence arrived.

The Key Pattern: When to Use Which Reading

Here is the rule that experienced learners internalize quickly. It is not 100% perfect, but it works for the vast majority of cases:

Let’s walk through this with the kanji 学 (gaku / mana):

• 学校 (gakkō) — two kanji, no hiragana → on’yomi: gaku + kō = school
• 学生 (gakusei) — two kanji, no hiragana → on’yomi: gaku + sei = student
• 学ぶ (manabu) — kanji + hiragana ぶ → kun’yomi: mana- = to learn

The same kanji, three different scenarios, and the pattern holds perfectly each time.

Another example with 行 (kō / iku):

• 旅行 (ryokō) — two kanji → on’yomi: ryo + kō = travel
• 行動 (kōdō) — two kanji → on’yomi: kō + dō = action, behavior
• 行く (iku) — kanji + hiragana く → kun’yomi: i- = to go

Common Kanji with Both Readings: Side-by-Side Comparison

The following table shows 20 frequently used kanji and one clear example of each reading. Learning these pairs builds strong reading intuition.

Special Cases: Kanji with Many Readings

Some kanji have so many readings that even native Japanese speakers occasionally need to double-check. These “difficult reading” kanji exist for historical reasons: borrowed at different times from different Chinese dialects, or given multiple native Japanese meanings over centuries.

生 (sei / shō / nama / i / u / ki / ha) — one of the most complex kanji

• sei — 学生 (gakusei, student), 人生 (jinsei, life)
• shō — 一生 (issō, one’s whole life)
• nama — 生ビール (nama bīru, draft beer)
• i(kiru) — 生きる (ikiru, to live)
• u(mareru) — 生まれる (umareru, to be born)
• ki — 先生気 (ikiki, vitality — in compounds)
• ha(yasu) — 生やす (hayasu, to grow/cultivate)

For a learner at N5–N4 level, do not try to memorize all readings of a kanji at once. Learn the reading in the context of whole words. When you learn 学生 as “gakusei,” you are learning the on’yomi of 生 through a real word. When you learn 生きる as “ikiru,” you are learning the kun’yomi through another real word. Context beats rote memorization every time.

Names are a separate system entirely. Japanese personal names and place names often use readings that are neither standard on’yomi nor standard kun’yomi. These are called nanori (名乗り). For example, the name 悟 is read satoru — a reading not found in dictionary entries for that kanji. Do not expect the standard rules to cover names.

Yuka

Wait — so I cannot always predict how a name is pronounced just from the kanji? That seems really hard!

Rei

You are right — and even native Japanese people sometimes cannot read an unfamiliar person’s name on the first try! It is perfectly acceptable in Japanese culture to ask how someone’s name is read. The phrase 「お名前の読み方を教えていただけますか」 is perfectly polite for this.

How to Know the Reading Without a Dictionary

You will not always have a dictionary open. Here are the practical signals that experienced learners use to guess readings on the fly.

Signal 1: Count the kanji in the word

If you see two or more kanji with no hiragana between or after them, on’yomi is your default guess. If you see a single kanji — especially if hiragana follows — go with kun’yomi.

Signal 2: Check for okurigana

Any hiragana attached to the end of a kanji is called okurigana. Okurigana almost always means the word is using kun’yomi. This applies to:

• Verbs: 食べる (taberu), 書く (kaku), 来る (kuru)
• Adjectives: 楽しい (tanoshii), 難しい (muzukashii), 大きい (ōkii)
• Nouns derived from verbs: 買い物 (kaimono, shopping), 飲み物 (nomimono, drink)

Signal 3: Days of the week are reliable on’yomi territory

The seven days of the week in Japanese are all Sino-Japanese compounds, making them perfect on’yomi practice material. Learn these and you have memorized the on’yomi for 日, 月, 火, 水, 木, 金, and 土 without extra effort.

Signal 4: Word register gives clues

On’yomi words tend to sound more formal or technical. If you are reading a newspaper headline, a medical term, or a legal document, on’yomi compounds dominate. In casual conversation about everyday objects and actions, kun’yomi words appear more often. This is not a rule you can always apply in real time, but it builds useful intuition over time.

Honest caveat: exceptions exist

The pattern “two kanji = on’yomi” has real exceptions. Some kanji compounds mix readings in ways that must simply be memorized:

• 今日 (kyō) — both kanji but the reading is kun’yomi-based (kon + nichi → kyō, a contracted form)
• 大人 (otona) — two kanji but the reading is purely kun’yomi (ō + tona)
• 山川 (yamakawa) — two kanji, but kun’yomi (yama + kawa)
• 東京 (Tōkyō) — on’yomi, as expected for a place name borrowed from Chinese

The pattern is a starting point, not a law. As your vocabulary grows, you will internalize exceptions naturally through exposure rather than rule-memorization.

Quick Quiz: Which Reading Is It?

Test your understanding with these questions. Answers are below — no peeking!

Question 1.
学校 (gakkō) uses the _____ reading of 学.
A) kun’yomi    B) on’yomi    C) nanori

Question 2.
飲む (nomu, “to drink”) uses the _____ reading of 飲.
A) on’yomi    B) kun’yomi    C) Neither — it has no reading

Question 3.
What is the strongest visual signal that a kanji word uses kun’yomi?
A) The word has three or more kanji    B) Hiragana (okurigana) is attached    C) The word appears in a newspaper

Question 4.
人口 (jinkō, “population”) uses on’yomi for both kanji. What are those readings?
A) hito + kuchi    B) jin + kō    C) nin + guchi

Question 5.
Which of these would most likely use kun’yomi?
A) 医者 (isha, doctor)    B) 大きい (ōkii, big)    C) 学校 (gakkō, school)

Question 6.
The name 田中 (Tanaka) is a Japanese surname. Its reading is:
A) On’yomi (den + chū)    B) Kun’yomi (ta + naka)    C) Nanori (special name reading)

Question 7.
Fill in the blank: 「月曜日」 (Monday) uses the _____ reading of 月, which is _____.
A) kun’yomi — tsuki    B) on’yomi — getsu    C) on’yomi — gatsu

Answers

1. B — on’yomi. Two kanji, no hiragana: the pattern points to on’yomi, and 学校 is gaku + kō.

2. B — kun’yomi. The hiragana む (mu) is okurigana, signaling kun’yomi. 飲む = no-mu.

3. B — hiragana (okurigana) is attached. This is the most reliable visual cue for kun’yomi.

4. B — jin + kō. 人 on’yomi = jin, 口 on’yomi = kō. (Hito and kuchi are the kun’yomi equivalents.)

5. B — 大きい (ōkii). The hiragana きい is okurigana, confirming kun’yomi. The other two words are kanji-only compounds using on’yomi.

6. B — kun’yomi (ta + naka). 田 = ta (paddy field), 中 = naka (middle, inside). This is a case of kun’yomi used in a compound, which is common for traditional Japanese surnames and place names.

7. B — on’yomi — getsu. Days of the week use on’yomi throughout. 月 as on’yomi = getsu (or gatsu for months: 一月 = ichigatsu).

Decision Flowchart: 「Which Reading Is This?」

Use this flowchart whenever you are unsure which reading to use for an unfamiliar kanji word.

Is this word a person's name or place name?
   YES → Use a dictionary or ask a native speaker.
          Names may use nanori (special readings).
   NO  → Continue below.
   |
   v
Does the kanji have hiragana attached directly after it (okurigana)?
   YES → Almost certainly KUN'YOMI.
          Examples: 食べる (taberu), 大きい (okii), 書く (kaku)
   NO  → Continue below.
   |
   v
Is this a single kanji standing alone?
   YES → Likely KUN'YOMI.
          Examples: 山 (yama), 水 (mizu), 火 (hi)
   NO  → Continue below.
   |
   v
Are two or more kanji written together with no hiragana between them?
   YES → Very likely ON'YOMI for all kanji.
          Examples: 学校 (gakko), 電話 (denwa), 大学 (daigaku)
   NO  → Continue below.
   |
   v
Does the word feel formal, technical, or academic?
   YES → Lean toward ON'YOMI. Verify with a dictionary.
   NO  → Lean toward KUN'YOMI. Verify with a dictionary.
   |
   v
Still unsure? Check a dictionary (Jisho.org is free and reliable).
On'yomi readings are shown in KATAKANA in Japanese dictionaries.
Kun'yomi readings are shown in hiragana.

One useful dictionary note: in Japanese dictionaries (and many apps), on’yomi are conventionally written in katakana and kun’yomi are written in hiragana. So if you see ガク next to a kanji, that is the on’yomi gaku. If you see まな (with a dot indicating the okurigana boundary), that is the kun’yomi mana(bu).

Yuka

This flowchart is so helpful! I feel like I can finally make educated guesses instead of just panicking whenever I see an unknown kanji.

Rei

Exactly! And the more vocabulary you absorb through reading and listening, the faster the pattern becomes automatic. You will start recognizing whether a word “sounds like” on’yomi or kun’yomi before you even think about the rules.

Which kanji reading do you find trickiest — on’yomi, kun’yomi, or name readings? Share your experience in the comments below. We read every response and often use your questions to shape future articles!

Keep Learning

Now that you understand how on’yomi and kun’yomi work, the best next step is to build your kanji vocabulary systematically. Start with the kanji on the JLPT N5 list — every single one appears in common words, and learning them through full words (not isolated characters) will reinforce both readings naturally.

あわせて読みたい

How to Study for JLPT N5: The Complete Beginner’s Guide You've decided to start learning Japanese — congratulations! Now someone mentions "JLPT N5" and suddenly you have a dozen questions: What is it? How hard is ...

Once you have the N5 kanji under your belt, move on to the N4 list. By the time you finish N4, the on’yomi vs kun’yomi distinction will feel intuitive rather than confusing.

あわせて読みたい

JLPT N4 Kanji List: All 166 Characters to Master You cleared JLPT N5. You can read hiragana and katakana, you know the basic 80 kanji, and you can survive a conversation about directions or ordering food. N...

If you are just getting started with JLPT preparation, the N5 kanji list gives you the essential 100 characters that form the foundation of everything above.

あわせて読みたい

JLPT N5 Kanji List: All 80 Characters with Readings, Meanings and Examples If you are preparing for the JLPT N5, kanji is one of the areas that trips up beginners the most. You open a textbook, see a wall of characters, and wonder w...

The most efficient approach: learn kanji inside real words rather than in isolation. Every time you encounter a new vocabulary word, notice whether it is a compound (likely on’yomi) or a single kanji with okurigana (likely kun’yomi). Over time, this awareness becomes automatic — and you will find yourself reading unfamiliar kanji words correctly far more often than you expect.