Japanese Writing System

Hello everybody,

I’m new to learning Japanese and it seems to me that I learn something new about the writing system every time I dive into that topic. Besides there were some questions about Kanji that came up doing my lessons and reviews on WaniKani. So I decided to take all my information about the Japanese writing system and put them in one place to get a better overview and understanding (especially which reading to use when).
Maybe this will be helpful to others, too, so I want to share it here:

Japanese has three kinds of characters: Hiragana, Katakana and Kanji. Advantage: there are no upper and lower case characters.

Hiragana: used for native Japanese words
There are 46 basic syllables and 23 additional sounds (see: Dakuten)

Katakana: used for writing loanwords and foreign names
There are 46 basic syllables and 23 additional sounds (see: Dakuten)

Hiragana and Katakana represent sounds and are referred to as “Kana”.

Japan didn’t have a written language as Chinese characters (Kanji) made their way to Japan. Kanji are Chinese writing symbols that represent meanings. Hiragana and Katakana evolved later in Japan based on simplified Kanji.

However there already existed a spoken language in Japan that was very different from Chinese. This is the reason for two different readings for Kanji: On’yomi and Kun’yomi. On’yomi is the original Chinese reading and Kun’yomi is the Japanese reading for a Kanji.

Joyo Kanji: 2.136 Kanji which are designated as most commonly used Kanji by the Ministry of Education

Then there are four types of Kanji:

  1. Pictograms: Kanji made from pictures (eg. 木 tree, 日 sun/day)
  2. Simple ideograms: Kanji that represent numbers or abstract concepts (eg. 三 three, 上 up/above)
  3. Compound ideograms: Kanji made from the combination of two or more Kanji (eg. 人 person + 木 tree --> 休 rest)
  4. Phonetic ideographic characters: Kanji that are made up of a meaning element and a sound element (eg. 日(sun) + 青 sei (blue) --> 晴 sei (clear sky))

There are some additional terms when it comes to the Japanese writing system:

Romaji: transcription of Kana to Latin letters

Dakuten: a little quotation mark/circle that modifies Kana (eg. は (ha) to ば (ba) and ぱ (pa))

Furigana: Hiragana above/beside a Kanji that represent the correct reading (depending on horizontal/vertical writing)

Rendaku: “sequential voicing”; changes to sounds to make words easier to say (eg. 人々 is ひとびと (hitobito) not ひとひと(hitohito))

Jukugo: compound words

Okurigana: Hiragana letters that stand after a Kanji (literally “letters which are sent out from the Kanji”)

Radicals (Bushu): smallest units of Kanji; they don’t have a real meaning and are combined to make Kanji

Now, which reading is used with a Kanji:


  • Chinese reading of a Kanji; “sound reading”
  • used when the Kanji is combined with another Kanji to form a compound word
  • used when no hiragana are attached to the Kanji
  • taught in WaniKani with Kanji

There can be multiple on’yomi readings for each kanji because they were introduced to Japan multiple times over the curse of a few hundred years. The different readings come from different provinces and dynasties and apparently all of them had slightly different ways to pronounce things.


  • Japanese reading of a Kanji
  • Meaning of Chinese character associated with Japanese reading equivalent
  • The way the Kanji is pronounced by itself
  • Words which contain only one Kanji
  • Jukugo words which have Hiragana attached to them
  • taught in WaniKani with Vocab

Body parts mostly use Kun’yomi reading.

When does the Rendaku appear?

  • Words that are duplicated get a Rendaku ((eg. 人々 is ひとびと (hitobito) not ひとひと(hitohito))
  • Rendaku is mostly used with Kun’yomi readings

There are no Rendaku changes in words if

  • the word already has a dakuten
  • the second element is a consonant sound
  • it is a foreign word as these are written in katakana and aren’t changed
  • it is a jukugo word (mostly, but there are of course exceptions)

And then there are a ton of exceptions that just have to be learned the hard way :wink:

(My resources were WaniKani, Genki, Tofugu, Kanjidamage and Wikipedia)

Did I miss something important? Did I mix up two different concepts? Any mistakes in this?
I hope this will help me to know when to use which reading ^^’


I do have a question about the Kanji type “Phonetic ideographic characters”: Is it always the right Kanji that carries the sound?

And how do you distinguish between words with the same sound in a conversation? For example こう can be
工 construction, industry
口 mouth (but in a conversation this will mostly be くち ?)
公 public
広 wide
行 go
交 mix
光 sunlight, light
(And I’m only level 5…) Is it really always clear which topic one is talking about? I can’t wrap my head around this.

Someone help me, please! :sweat_smile:


These are on’yomi that will mostly appear along side other kanji, forming jukugo words, so it won’t be こう by itself. You’ll still have homophones, of course, but you’ll figure out through the context. Just like English has the pairs know/no, cell/sell, meet/meat that sound the same but you know what people are saying from the context.


so did the Chinese curse the Japanese to learn kanji? :stuck_out_tongue:

By the way, that little circle in ぱ、ぴ、ぷ、ぺ、ぽ is known as a handakuten/maru, but I suppose it’s the same general category :sweat_smile:

This is basically what WaniKani uses the word “radical” to mean, but be aware that it’s not quite the same as the usage of “radical” you’ll see elsewhere.

If you say 部首 (ぶしゅ) to a Japanese person, they will understand that to mean the single representative element for a particular kanji used to look it up in a kanji dictionary. To a Japanese person, radicals are not “combined to make kanji” because of the fact that each kanji can only have one radical. This definition isn’t terribly useful to most people, but if you’re trying to compile somewhat “official” summaries of the elements of Japanese writing, this is the more conventional definition.

By the way, that little circle in ぱ、ぴ、ぷ、ぺ、ぽ is known as a handakuten/maru,

Similarly the dakuten mark is known as tenten. The natives I’ve talked with know tenten and maru, but not dakuten and handakuten, so I suspect those are rather technical.

When I first realized the only difference between sounds, when using tenten and maru, was mostly the use of voice, I was amazed, as I was never taught that learning English. My entire life, I was unaware of a deep fundamental connection existing between the different sounds I was making everyday.

Thank you all!

Well, that seems to be the case :sweat_smile:

This is a really great overview! I’ll have to keep it in mind whenever I find someone that doesn’t know their わ’s from their ワ’s.

Also this is not entirely true, WK will teach the most common reading for a single kanji (sometimes two), and it will mostly be ON, but sometimes KUN.


And some vocab still uses On, or a mixture of On & Kun.

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Yeah, you don’t have to look far. For instance, 本, which everyone knows if they’ve taken any Japanese at all, is read with the onyomi, even though it’s a solo kanji.

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Not to mention seemingly random dakuten

It’s a pretty complete overview, but to be even more precise, you could speak about the writing of the long vowel sounds and how the differ in hiragana and katakana, the use of っ to write the “pause” in words (don’t know the proper term in english), kana digraphs (きょ, しゃ etc.), the katakana exclusive digraphs (ファ, ヴイ, ティ…) used only for loanwords…
These notions are really important as they are required to properly understand everything.
Oh, and you could also add that a lot words referring for instance to animals are often written in katakana and not in kanjis, even if they are not a loanword: you’ll read more サイ more than 犀 for a rhino. Hiragana are also used to write most adverbs ( そのまま, たくさん…) because their kanji writings tend to be forgotten.

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The “radical” part doesn’t need to be the left one, it can also be in other positions, for example:

  • 刊 (publish, carve, engrave): the right side (刂) is the radical, 干 (かん) is used phonetically to indicate “to dry”, “to carve”
  • 星 (star, spot, dot, mark): radical is 日, 生 (せい) is used phonetically to indicate clear.

I think this part may be a bit misleading, you could think that blue+sky leads to clear sky, but when a kanji part is used phonetically that part could depict anything, as long as it is reads せい (-> clear) as in the example above.

Thank you all very much!
So much new information

That’s very interesting. Any ideas why that is like that?

That example is from Genki. I can’t wrap my head around these at the moment so I couldn’t come up with an own example. Don’t know how exactly these Kanji work.

The katakana tend to be used to talk about species in general (“dogs are mammals”), and kanji tend to be used to refer to individuals (“I named my dog Rex”). I only recall my teacher saying that, so I’m lacking a good written reference. I’ll search about it when I have time. :slight_smile:

Katakana can also be used to denote that a word is emphasised, like bold or italics. Sometimes it’s used instead of using a kanji. Sometimes people just feel like using katakana. It’s very ¯_(ツ)_/¯ sometimes.

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There is an interesting article on the satori reader help page with more info:
https://www.satorireader.com/help#kanji-kana-representation (maybe you need a free account to see it)
For the Rhino case it says that the word is emphasized similar to italics or the writer feels that the kanji is too uncommon [and they don’t want to appear too flashy by showing off their fancy kanji knowledge or embarrassing the reader].

Yes, I have the feeling that I saw that example text somewhere before and remember that didn’t get at all what phonetic meant at the time. Especially because phonetic refers to Chinese phonetics at the time the kanji were developed, so not even the sound might have anything to do with the Japanese reading.

I’m not even sure if 青 was only originally used phonetically in the Genki case, there just may be better examples. Genki has a very limited pool of kanji, probably they just picked the best option.

Something weird might happen occasionally though. See 神道, where 道 loses the tenten. Reverse rendaku? Perhaps I’m just ignorant though.

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I still don’t know how to read Kanji the right way. I’ll try to explain what I mean:

I have been watching Naruto lately and I’m always thrilled when I see a Kanji in the background or so and recognize it. But…


Thanks to Wanikani I know
四 = よん = yon => four
代 = だい = dai => substitute, replace, period, age
目 = め = me => eye
火 = ほ = ho => fire
And I suppose the last one is read as かげ (kage) :laughing:

So we have “yondaime hokage”. Okay. That’s how we say it. But what do the Kanji mean?
If I wouldn’t know what a hokage is then what would I guess? Is he the “fourth period watching over fire whatever-that-last-kanji-means”?

Does anyone understand what I want to ask? :sweat_smile:

And how on earth would I know that “fire” is read as “ho” in this case and not “hi” if I didn’t know the sound before seeing the word?

I’m confused!

I don’t think you reasonably can. Just like you can’t know that the last e in catastrophe isn’t silent unlike most other words ending in -e. :slight_smile:

Some words you can guess from the spelling how they’re read, others you’ll just have to learn.

EDIT: I didn’t know the word 火影, but it can be looked up in the dictionary: http://jisho.org/search/火影

Also, you are correct that 影 means shadow.