You look at a kanji, recognize the shape, that you've seen it before... but get stuck when it's time to read it. The correct reading of a kanji is not always intuitive, and yes, there are various ways to read it. In Japanese, the same character can have different readings depending on the context, the word, and even the combination with other kanjis. This happens because of the on and kun readings, among other nuances.
But take it easy. There is logic behind this apparent confusion. And understanding this logic is the first step to mastering readings and stopping guessing. Let's explore each of the factors that influence the correct reading of a kanji, with practical examples, cultural insights, and tips to make your learning easier.
The question that won't go away: can we know when to use kun-yomi or on-yomi just by looking? The answer is: almost. With practice, patterns, and observation, you'll get there.
Table of Contents
Kun and on readings: what they are and when to use them.
First of all, you need to understand that the kanji came from China, but the Japanese language already existed. This means that each character was adapted, gaining at least two forms of reading: a native one (kun-yomi) and one of Chinese origin (on-yomi).
The kun-yomi is the original Japanese reading, usually used when the kanji appears alone or in more “Japanese” words. The on-yomi is the adapted Chinese reading, and it mainly appears in compounds of two or more kanjis.
We already have a complete article discussing reading kun yomi and on yomi. But let's make a small summary in this article. See the example with the kanji 山 (mountain):
- Kun-yomi: yama (mountain) → Climb the mountain (subir a montanha)
- On-yomi: Sansan) → Mount Fuji (Fuji-san, Mount Fuji)
Did you notice that the reading changes depending on the usage? This is the general rule, but as always, Japanese likes exceptions. There are words with mixed readings, and some forms that only appear in proper names or fixed expressions.
When to use which?
- Kanji alone → usually uses kun-yomi
- Two kanji together → usually uses on-reading
- With okurigana (kana that accompany the kanji) → kun-yomi
- Technical or Sino-Japanese words → on-reading
But that's not all. Some words have more than one valid reading, depending on the context. Therefore, it's not useful to memorize them in isolation. You need to see the kanji in action.

Radicals: the key to understanding and memorizing
The radicals (bushu) are the building blocks of kanji. They provide clues about the meaning, and sometimes even about the reading. Knowing how to identify the radicals can save a lot of time when trying to guess what a kanji means.
Think of radicals as LEGO pieces. Together, they form a more complex character, but each piece still carries its meaning. A clear example is the radical 氵(sanzui), which appears in kanjis related to water:
- Sea (うみ, ocean, Mar)
- river (かわ, river, river)
- wash (あらう, arau, wash)
Even if the reading is not the same, the radical helps you visually associate the kanji with an idea.
Some radicals also indicate reading.
It is rare, but it exists. Some radicals or components carry phonetic clues. One example is 青 (ao, blue), which appears in:
- Seisui (clean)sei, sei) — clean
- clearsei, sei) — clean time
These kanjis share part of the reading because of the phonetic component 青. But be careful: this pattern is not guaranteed. Use it as a hint, not as a fixed rule.

Reading in proper names: the treacherous part
If you've ever tried to read Japanese names, you know what comes next. The kanjis in proper names can have readings that stray from any pattern. This happens because names allow more freedom in the choice of readings, including using nanori — readings used only in names.
For example, the kanji 一 can be read as:
- one (one, reading on)
- ひと (human)hito, kun reading)
- kazukazu, nanori reading)
So, if you see 一美, it could be Kazumi, Hitomi, Ichimi... without context, there's no way to know for sure. The only solution? See how the person reads their own name. It's that simple.
Practical tip: when studying names, memorize them as a unit. Don't try to decipher them piece by piece — it's like trying to guess a Wi-Fi .

Other readings and special cases
In addition to on, kun, and nanori, there are other surprises in the world of kanjis. Some gain special readings in fixed words, idiomatic expressions, or due to historical changes in language.
A good example is 今日. The kanjis literally mean "this day," but the reading is きょう (kyou), which does not exactly correspond to any of the traditional readings of 今 (ima) or 日 (hi/nichi).
These cases are called 読み方特有 (tokuyuu yomikata), meaning specific readings. They are exceptions that need to be memorized, but they appear frequently.
Another trap is the ateji — kanji used only for their pronunciation, with no connection to the meaning. One example is 寿司 (sushi), where the kanji has nothing to do with raw fish. They are used solely for their sound.
Want a way to avoid confusion? Use reliable dictionaries and tools like jisho. They show all the possible readings of a kanji, with practical examples and even the radicals used.
Tips for discovering the reading of a kanji
You don't need to memorize all the readings. The secret is to learn the patterns and train your intuition. Here are some strategies that work:
- Analyze the context: what comes before and after the kanji changes everything.
- See if there is okurigana: if there is, it probably is kun-yomi.
- Look for the type of the word: technical, abstract, or compound words tend to use on-reading.
- Use the most common reading first: some kanjis have more common readings — start with them.
- Study by words, not by isolated kanjis: memorize complete words and their real readings in daily life.
Additionally, listening to spoken Japanese helps with retention. Watch anime, dramas, listen to podcasts. Try to repeat sentences with the kanji you are studying. This improves your memorization and your confidence.