Japanese Keyboard Layouts

Here's a introduction to Japanese writing system, Japanese input methods, and Japanese keyboard layouts.

Japanese Writing System

First, you need to learn a bit about Japanese writing system before you can learn about how Japanese is typed on keyboard.

Japanese writing uses the following characters:

• Japanese Phonetic alphabets, called kana (仮名).
• Chinese characters, called kanji (漢字).
• English alphabets, called Romaji. (Romaji literally means “Roman characters ”.)

Of the kana, there are 2 types:

• Hiragana (ひらがな, 平仮名). → Hiragana looks curvy.
• Katakana (カタカナ, 片仮名). → Katakana looks angular. Katakana is used for place names, company names, imported words, emphasis, etc. Purpose of Katakana is somewhat like English uppercase letters.

There are total of 48 hiragana in modern Japanese. Same total for katakana.

Japanese kana: hiragana (left) and katakana (right)

♦	–	k	s	t	n	h	m	y	r	w
a	あア a	かカ ka	さサ sa	たタ ta	なナ na	はハ ha	まマ ma	やヤ ya	らラ ra	わワ wa
i	いイ i	きキ ki	しシ si	ちチ ti	にニ ni	ひヒ hi	みミ mi	♦	りリ ri	ゐヰ wi
u	うウ u	くク ku	すス su	つツ tu	ぬヌ nu	ふフ hu	むム mu	ゆユ yu	るル ru	♦
e	えエ e	けケ ke	せセ se	てテ te	ねネ ne	へヘ he	めメ me	♦	れレ re	ゑヱ we
o	おオ o	こコ ko	そソ so	とト to	のノ no	ほホ ho	もモ mo	よヨ yo	ろロ ro	をヲ wo

n
んン n

The Dakuten Diacritic Mark

Dakuten ゛ is a diacritic mark that often occures for many hiragana.

When it appears on a hiragana, it means that the consonant of the syllable should be voiced.

Character Frequency in Japanese

In formal writing, such as newspaper or books, about half are kanji, and other half are hiragana.

Japanese Character frequency

Characters	%
Kanji	41.38
Hiragana	36.62
Katakana	6.38
Punctuation and symbols	13.09
Arabic numerals	2.07
Latin letters	0.46

Source, Japanese newspaper Asahi Shimbun from the year 1993 (around 56.6 million tokens). [Chikamatsu, Nobuko; Yokoyama, Shoichi; Nozaki, Hironari; Long, Eric; Fukuda, Sachio (2000). A Japanese logographic character frequency list for cognitive science research. Behavior Research Methods, Instruments, & Computers. 32 (3): 482–500.] via Wikipedia Japanese writing system

Here's sample of Japanese writing, from Wikipedia Japanese article on keyboard:

キーボード（英: Keyboard）は、コンピュータへの入力機器の一つであり、手指でキーを押すことでコンピュータへ文字信号などを送信するもの。様々なソフトウェア上で文字入力を基本とした機器であるが、コンピュータ (OS) の操作全般にも用いられる。

日本語における 鍵盤はkey boardからの訳語であり両者は本来的に同一のものである。欧米においては鍵盤楽器のカラクリを応用した機械式タイプライターを経て、タイプライターのインタフェースを模した電子的入力機器へと連続的に発展していった歴史的経緯により一連の概念として理解されるが、タイプライターの普及が限定的に留まった日本の社会通念においては、楽器の鍵盤と入力機器のキーボードとは断絶しており個別に扱われることが多く、電子楽器のキーボードでわずかに関連性が示される程度である。

[2017-07-16 キーボード (コンピュータ)]

Those complex looking ones are kanji (Chinese characters). The cursive looking ones are hiragana, and angular ones are katakana.

In informal writing, such as online chat, less kanji is used.

To read Japanese newspaper or books, you need to know 2k kanji. See Jōyō kanji (常用漢字)

In comparison, for Chinese people reading Chinese newspaper, 3500 characters are needed. [〈通用规范汉字表〉 [Table of General Standard Chinese Characters]. Ministry of Education of the People's Republic of China. 18 Jun 2013.]

See also: How to Tell the Difference Between Chinese, Japanese, Korean?

How to Type Japanese

So, writing Japanese is hard. You have:

• ~2 thousand kanji.
• ~80 hiragana. (48 plus ~30 variation with voiced sound mark.)
• ~80 katakana.
• 52 English letters (26 lowercase and 26 uppercase.)
• digits 0 to 9, and punctuation.

There are 2 major systems to input hiragana:

• Romaji input system: Type the English letters that corresponds to the hiragana reading, and it becomes a hiragana character. Each hiragana needs 2 English letters.
• Kana input system: The keyboard keys are mapped to hiragana directly. Press the key to insert that hiragana character. (some kana character needs Shift key to enter.)

To input kanji, press a “conversion” key , then it'll convert previous kana character or phrase to kanji. Because there are many homonyms, typically a selection will popup to let you pick the correct kanji.

To input katakana, either switch to a dedicated katakana mode, or, the katakana shows as a choice among kanji character choices.

To input English letters (romaji), switch to romaji mode that lets you enter the English letters as is.

That's the basics.

Most people in Japan, use romaji method to input Japanese. That is, on a normal PC keyboard with QWERTY layout, type the English letters of the kana reading, and it becomes the hiragana character, and press a key to convert the previous word to kanji or katakana.

This is a inefficient method, but requires no learning.

See also: Chinese Input Methods

Special Keys on Japanese Keyboards

Keyboards sold in Japan usually have special keys.

They are not necessary, as you can type Japanese with US keyboard. When a keyboard doesn't have these special keys, usually Space, Return, or a Ctrl combination works.

Here's the keys.

• 変換 → reads “henkan”, meaning “conversion”. Convert to kanji. Sometimes the key is labeled like a circular arrows 🗘. If the key doesn't exist, usually Space does the same.
• 無変換 → reads “muhenkan”, meaning “no conversion”. If the key doesn't exist, usually Return does the same.
• かな or kana → kana mode.
• ひらがな → hiragana mode. Or Ctrl+Caps Lock
• カタカナ → katakana mode.
• ローマ字 → rōmaji mode.
• 英数 → alphanumeric mode. (if not exist, usually Caps Lock does the same. For actual caps lock, press Shift+Caps Lock)
• 半角/全角 → Half-width/Full-width. Toggles the font between full-width and half-width of English letters and punctuations.

In Japanese and Chinese, each character is a square. Text are aligned vertically, forming a grid. the width of English letters are not the same as Japanese and Chinese. So, there's the idea of full-width English alphabet characters, where each character has the same width as the square, so that the text has columns aligned.

[see Ｕｎｉｃｏｄｅ　Ｆｕｌｌ－Ｗｉｄｔｈ　Ｃｈａｒａｃｔｅｒｓ]

So, there's usually a key 半角/全角 or software toggle for user to chose between full-width or half-width. Half-with means using proportional font for English.

• 半角 → half width. (use proportional font) Sometimes shown as a crescent moon icon 🌙 or ☽ or ☾
• 全角 → full width monospace font. Sometimes shown as a white full moon circle 🌕.

Note: Full-width English letters in Japanese text is not necessarily preferred, since English in full-width doesn't look good.

[see Tiny Space Bar on Japanese Keyboards]

Japanese Keyboard Layouts

There are many ways to arrange the English letters on keyboard. And there are many ways to arrange the kana on keyboard too. So, there are many different layouts.

(Most of the following is base on http://www.esrille.com/keyboard/layouts.ja-jp.html)

See also: Esrille New Keyboard Review

Here are the different layouts:

• QWERTY JIS → Romaji input. Qwerty layout.
• M-type → Romaji input. Efficient layout. Home row keys are {e u i a o, k s t n h}.
• JIS X6004 → Kana input. Efficient kana layout. Use prefix shift. Dedicated dakuten key. Qwerty layout for English.
• Nicola (thumb-shift) → Kana input. 2 special Thumb-shift modifier keys. Kana with dakuten are typed by pressing the thumb-shift of the other hand. Qwerty layout for English.
• TRON → Kana input. Efficient kana layout. English layout is Dvorak. 2 special Thumb-shift modifier keys. Kana with dakuten are typed by pressing the thumb-shift of the other hand.
• New Stickney Layout → Kana input. Use prefix shift. Dedicated dakuten key.

QWERTY (JIS) Layout

This is the standard, most popular layout used in Japan. It is basically the same as USA keyboard.

You use English letters to type kana, then press a key to convert previous kana to kanji if necessary.

Every kana requires 2 keystrokes (2 English letters).

This is the least efficient method and layout.

[see The Idiocy of Happy Hacking Keyboard]

M-type Layout

M-type input system:

1. Use English letters to input Kana.
2. The English alphabet are arranged to make it easier for Japanese kana. For example, left hand home row is {e u i a o}, and right hand home row is {k s t n h}. This latter is the order of kana.

M-type input system and keyboard was designed by Dr Masasuke Morita at NEC in 1983.

JIS X6004 Layout

JIS X6004 is a very efficient layout.

It is kana based input. Each key types a kana directly.

The kana are arranged according to frequency and ease of the key-press position.

[see Japanese Hiragana Frequency Table]

The Shift key act as prefix key. That is, press it, release it, then the next key press will be effected.

When Shift key is prefixed, a different kana is typed. (Left Shift and right Shift are not differentiated.)

A dedicated key is used for the Dakuten ゛. (it's on the L key)

JIS X6004 was a Japanese industrial standard Kana layout established in 1986 to amend various issues in the current, old JIS standard Kana layout. While its technical design was superb for professional typists, JIS X6004 was abandoned as a JIS standard in 1999 due to its unpopularity in the market.

JIS X6004 allows a shift key to be placed in the center of the keyboard where a space-bar is placed. Since white space characters appear far less frequently in Japanese than in English, the same typing method can be used both in Japanese and English with this JIS X6004 configuration.

We could see JIS X6004 as a Japanese Dvorak or Colemak layout, and the current JIS standard Kana layout as QWERTY. Today its superior technical design has been re-evaluated as it becomes easy to scan and analyze huge Japanese texts and n-grams using personal computers. Even though JIS X6004 is no longer a JIS standard, it is actually still in use and its variations are also being developed by the enthusiasts.

Nicola Layout (Thumb-Shift)

In Nicola Layout (aka Thumb-Shift) layout:

1. Each key corresponds to a kana character.
2. 2 special shift keys: left thumb-shift key and right thumb-shift key. Each is a independent modifier key.
3. Only 3 rows are used for kana, each row has 5 keys per hand. So, left hand has 15 keys, right hand has 15 keys, total 30. Multiply by 2 thumb-shift keys, you have 90 possibilities, enough for all kana letters.

Note: the 2 distinct thumb-shift keys means, some character need to be typed using the same hand, thumb holding the shift.

Nicola became quite popular in the 1980s, and still has great number of users.

Yasunori Kanda and others at Fujitsu developed Thumb-Shift layout in the late 1970s.

[see Japan Thumb-Shift Keyboard]

In Nicola layout, Kana characters with a Dakuten ゛ can be typed by pressing the Kana character key and the thumb shift key at the other side at the same time.

Example:

• け + Shift ⇒ げ
• と + Shift ⇒ ど

TRON Kana Layout (Dvorak)

TRON is input system, layout, and a special ergonomic keyboard.

TRON input system:

1. Is kana input system. That is, keys correspond to hiragana directly.
2. Uses Dvorak layout for English. [see Dvorak Keyboard Layout]
3. kana arrangement is optimized for efficiency.
4. Tron uses left shift and right shift to input different hiragana. The left/right shift are positioned for the thumbs.
5. left/right shift is also used to input left/right brackets on the number row, and different punctuations on other keys.

The TRON Kana layout was developed by Prof. Ken Sakamura in the TRON keyboard sub-projects of the TRON project in the mid 1980s.

TRON Kana layout has a quite high efficiency regarding the number of required key touches to input Japanese texts.

New Stickney Layout

This is a new efficient layout.

• Kana input. The kana are arranged efficiently.
• Use pre-shift key. To press a shifted kana, press Shift, release, then press the kana key.
• A dedicated key for dakuten ゛. (on the L key) Press it after the kana.

• か゛ → が

see https://esrille.github.io/ibus-replace-with-kanji/layouts.html