A Proposal for Romanization of Japanese
extending Hepburn System

Introduction

This document describes how to spell Japanese language with Roman Letters. This is written as a reference to revise ISO 3602.

Syllabary 1

Syllabary 1 is used to spell ordinary Japanese documents.

Syllabary 1 for native words
a e i o u ya yo yu
a e i o u ya yo yu
b ba be bi bo bu byaビャbyoビョbyuビュ
chchaチャ chichoチョchuチュ
d da de do
f fu
g ga ge gi go gu gyaギャgyoギョgyuギュ
h ha he hi ho hyaヒャhyoヒョhyuヒュh(*1)
j ja ジャ ji jo ジョju ジュ
k ka ke ki ko ku kyaキャkyoキョkyuキュ
m ma me mi mo mu myaミャmyoミョmyuミュ
n na ne ni no nu nyaニャnyoニョnyuニュn(*2)
p pa pe pi po pu pyaピャpyoピョpyuピュ
q q(*3)
r ra re ri ro ru ryaリャryoリョryuリュ
s sa se so su
shshaシャ shishoショshuシュ
t ta te to
ts tsu
w wa
z za ze zo zu
(*1) Prolonged Vowels
The letter "h" is used to spell prolonged vowels. The circumflex or the macron is usually substituted for the letter "h". It is omitted in the Japanese passport guideline. Prolonged vowels are sometimes spelled as double vowels or follow Japanese orthography of Kana script.
(*2) The Nasal Syllable
The letter "n" is used to spell the nasal syllable. The letter "m" may be substituted for the letter "n" before the letters "b", "m", and "p".
(*3) The Glottal Stop
The leter "q" is used to spell the glottal stop. When the glottal stop is located before a consonant, it usually changes to a prolonged consonant. The letter "q" before a consonant may be replaced with double consonants such as "kk", "pp", "ss" and "tt". Exceptionally, the consonant "ch" follows "t" as "tch". When a vowel or a semivowel needs to start a new syllable at the middle of a word, the glottal stop letter "q" may be inserted to avoid ambiguity. Vowels is "a", "e", "i", "o", and "u". Semivowels are "w" and "y". The apostrophe is usually substituted for the letter "q". It is omitted in the Japanese passport guideline. If the following exceptional sequences appear, the letter "q" is literally used as the glottal stop.

Syllabary 2

Syllabary 2 is used to spell Japanese documents including loanwords. This syllabary complements most of the blank cells of Syllabary 1.

Syllabary 2 for loanwords
a e i o u ye yo yu
+ + + + + ye イェ+ +
ch+ cheチェ+ + +
d + + di ディ+ du ドゥ dyuデュ
f fa ファfe フェfi フィfo フォ+ fyoフョfyuフュ
gwgwaグァgweグェgwiグィgwoグォ
h + + + + hyeヒェ+ +
j + je ジェ+ + +
k + + + + + kyeキェ+ +
kwkwaクァkweクェkwiクィkwoクォ
n + + + + + nyeニェ+ +
s + + si スィ+ +
sh+ sheシェ+ + +
t + + ti ティ+ tu トゥ tyuテュ
tstsaツァtseツェtsiツィtsoツォ+
v va ヴァve ヴェvi ヴィvo ヴォvu vyoヴョvyuヴュ
w + we ウェwi ウィwo ウォ
z + + zi ズィ+ +

Syllabary 3

Syllabary 3 may be used to spell classic Japanese documents and grammatical documents. This syllabary represents the real sound of the Kana script when it was invented.

Syllabary 3 for classic words
a e i o u ya yo yu
d + + * di + * du dyaヂャdyoヂョ* dyuヂュ(*1)
gw* gwaグヮ* * * (*2)
h + + + + hu + + +
kw* kwaクヮ* * * (*2)
s + + * si + + syaシャsyoショ syuシュ(*3)
t + + * ti + * tu tyaチャtyoチョ* tyuチュ(*3)
w + * we * wi * wo (*2)
z + + * zi + + zyaジャzyoジョ zyuジュ(*3)

Appendices

Consonants
labialalveolarpost-
alveolar
palatalvelar glottal
VLV VLV VLV V VLV VL
plosive p b t d k g q
affricate ts ch
fricative f v s z shj h
nasal m n
tap and flap r
approximant w y
VL: voiceless, V: voiced.
Vowels
frontcenterback
high i u
middlee o
low a
Kana Syllabary and the Order
a i u e o kakikukekosashisusesotachitsutetonaninuneno
Katakana
Hiragana
hahifuhehomamimumemoya yu yorari ru rerowawi wewon
Katakana
Hiragana

References