How to read and write in Japanese

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English • ‎日本語 • ‎한국어 • ‎中文(中国大陆)‎

This guide aims at explaining how to read and write in Japanese on a non-Japanese system. Please feel free to amend it based on personal knowledge or experience.


In order to support Japanese language and characters, a number of required tools, libraries and capabilities need to be installed on the system.

Japanese fonts

Most non-Japanese systems have no Japanese fonts installed. Whenever a user tries to enter Japanese characters from the keyboard, they will only see small rectangle boxes in place of the characters on the screen.

Input method

To read and write in Japanese, the first thing that is needed is a way to enter Japanese characters with the keyboard. This is done via a piece of software usually called an input method. At the moment, for the Japanese language, there are 2 such common methods: anthy and mozc.

With such a software component typing "ta" on the keyboard will input the kana into the word processor. Some simple manipulation that is relevant to the way the input method works, will permit to easily switch from the hiragana to the katakana .

In a similar way typing "nihon" will input にほん and an other simple manipulation will permit to turn this to the kanji version of this word, 日本.

It is not the purpose of this guide to describe in detail how the "anthy" or "mozc" input methods work. Please refer to the documentation of these software components.


On top of this users also need a way to switch from the input method normally used for the primary language to the one needed for the Japanese language. This functionality is provided by another piece of software called an IME (Input Method Editor) such as app-i18n/ibus, app-i18n/scim or app-i18n/fcitx.

Once installed, this allows users to switch from one language's input method to the Japanese input method using a key combination or using the mouse to select a relevant icon in the icon tray.


Japanese fonts

As a minimum, install the media-fonts/kochi-substitute package.

root #emerge --ask kochi-substitute

Additionally, the following packages are also available:

Input tools

It is recommended to use ibus instead of scim.

To install ibus, install app-i18n/ibus-anthy:

root #emerge --ask ibus-anthy


mozc is provided through the app-i18n/mozc package.

mozc has a better reputation than anthy though anthy has been proving working fine for years now. Among pros for mozc, there are the fact that it shows the candidates instantly during typing and has a better learning system in order to present the user the best candidates depending on the user's habit and context. It also provides the ATOK mechanism for quickly change an hiragana input to katakana (e.g. F7 as default before hitting space) or to other modes.
When trying to use mozc some problems might occur. After selecting mozc as an input method in the ibus-preferences graphical utility, the mozc icon in the keyboard icon tray might not be visible. Open the gnome settings --> Countries & Languages, remove all Japanese input methods (in this case "anthy") and add "Japanese(Mozc)".

Launching the ibus daemon at login time

Add these lines to the ~/.xprofile file and log out/log in again.

FILE ~/.xprofile
export GTK_IM_MODULE=ibus
export QT_IM_MODULE=ibus
export XMODIFIERS=@im=ibus
ibus-daemon -drx

This will allow the ibus daemon to start at login time.


To configure the Input Method Editor, use the following command as a standard user

user $ibus-setup

Alternatively, when using GNOME, type "ibus" in the search bar and launch "ibus-preferences".

In the dialog box that appears, click on the Input method tab and add the "japanese-anthy" method. Then return to the General tab and define a key combination as a keyboard short cut for switching the input method.


Here are some additional requirements to write Latex files in Japanese.


When using editor aiming at writing Latex files such as TexMaker or TexStudio, ibus crashes each time a Latex command is entered (specially after entering the { char). To solve this kind of malfunctioning install app-i18n/ibus-qt:

root #emerge --ask app-i18n/ibus-qt

CJK and xetex support

In order to write Japanese chunks in Latex files, add support for CJK languages and for [xetex] in Texlive.

This can be accomplished by adding or modifying the following lines in /etc/portage/package.use:

FILE /etc/portage/package.use/latexEnabling cjk and xetex support
app-text/texlive cjk xetex
app-text/texlive-core cjk xetex

Then reinstall the packages:

root #emerge --ask --newuse app-text/texlive app-text/texlive-core

Here is a working short LaTeX sample:

FILE japanese.tex
\section{One simple example}
But I can also write with latin characters
In the \begin{CJK}{UTF8}{min} command in the example above, the third argument defines the font. Here {min} is used for Mincho, but other supported fonts are Gothic ({goth}) and Maru Gothic ({maru}).

Editor configuration

To compile and visualize the output of the sample above Texmaker or Texstudio editor needs to be configured properly.

Open Texmaker, and go to Options -> Configure Texmaker. Under the Commands tab change the following:

  • At the LaTeX line, change "latex" with "platex".
  • At the Dvipdfm line, change "divipdfm" with "dvipdfmx".

Through the Fast compile tab, choose "Latex + Dvipdfm + View PDF".

Finally go to the Editor tab, choose UTF8 encoding and deselect On the fly on the dictionary line.

See also