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Japanese writing
Components
Kanji Stroke order Radicals Jōyō kanji list Kyōiku kanji Tōyō kanji Jinmeiyō kanji Hyōgai kanji
Kana Hiragana Hentaigana Katakana Man'yōgana Sōgana Gojūon
Typographic symbols Japanese punctuation Iteration mark
Uses
Syllabograms Furigana Okurigana Braille
Transliteration
Rōmaji Hepburn Kunrei-shiki / ISO 3602 Nihon-shiki JSL Wāpuro (keyboard input)
Cyrillization Polivanov system
v t e

Nihon-shiki (Japanese:日本式ローマ字,Hepburn:Nihon-shiki rōmaji;lit. 'Japan-styleRoman letters') is aromanization system for transliterating the Japanese language into theLatin alphabet. Among the major romanization systems for Japanese, it is the most regular one and has an almostone-to-one relation to thekana writing system. Its name is renderedNihonsiki in the system itself.

Nihon-shiki was invented by physicistAikitsu Tanakadate (田中館 愛橘) in 1885,^[1] with the intention to replace theHepburn system of romanization.^[2] Tanakadate's intention was to replace the traditionalkanji andkana system of writing Japanese completely by a romanized system, which he felt would make it easier for Japan to compete with Western countries. Since the system was intended for Japanese people to use to write their own language, it is much more regular than Hepburn romanization, and unlike Hepburn's system, it makes no effort to make itself easier to pronounce for English-speakers.^{[citation needed]}

Nihon-shiki was followed byKunrei-shiki, which was adopted in 1937, after a political debate over whetherNihon-shiki orHepburn romanization should be used by the Japanese government.^[1]Kunrei-shiki is nearly identical toNihon-shiki, but it merges syllable pairs di/zi ぢ/じ, du/zu づ/ず, dya/zya ぢゃ/じゃ, dyu/zyu ぢゅ/じゅ, dyo/zyo ぢょ/じょ, wi/i ゐ/い, we/e ゑ/え, kwa/ka くゎ/か, and gwa/ga ぐゎ/が, whose pronunciations in Modern Standard Japanese are now identical. For example, the word かなづかい, renderedkanadukai inNihon-shiki, is pronounced askanazukai in modern Japanese, and is romanized as such in Kunrei. TheInternational Organization for Standardization has standardized Kunrei-shiki, under ISO 3602. TheJSL system, which is intended for use instructing foreign students of Japanese, is also based onNihon-shiki. However,some Japanese-speakers still distinguish di from zi and du from zu and soNihon-shiki spelling is not entirely obsolete.

Nihon-shiki is considered the most regular of the romanization systems for the Japanese language because it maintains a strict "one kana, two letters" form. Because it has unique forms corresponding to each of the respective pairs ofkana homophones listed above, it is the only formal system of romanization that can allow (almost) lossless ("round trip") mapping, but the standard does not mandate the precise spellings needed to distinguish ô 王/おう, ou 追う/おう and oo 大/おお.

• In the table above, characters inred are obsolete in modern Japanese.
• UnlikeKunrei-shiki andHepburn:
  • Even whenhe (へ) is used as a particle, it is written ashe, note.
  • Even whenha (は) is used as a particle, it is written asha, notwa.
  • Even whenwo (を) is used as a particle, it is written aswo, noto.
• Syllabicn (ん) is written asn before consonants but asn' before vowels andy.
• Much likeKunrei-shiki:
  • Long vowels are indicated by acircumflex accent, for example: longo is writtenô. Similarly, Hepburn uses amacron:ō.
  • Geminate consonants are always marked by doubling the consonant following thesokuon (っ).

• List of ISO romanizations

• Romanization of Japanese
• ISO 3602
• Japanese writing system

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